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Thursday, April 3, 2008Windows System Administrator Interview questions
What is Active Directory?
Ans. Active Directory is a Meta Data. Active Directory is a data basewhich store a data base like your user information, computer informationand also other network object info. It has capabilities to manage andadministor the complite Network which connect with AD.
Ans: Active Directory directory service is an extensible and scalabledirectory service that enables you to manage network resourcesefficiently.
Ans:Active Directory is directory service that stores information aboutobjects on a network and makes this information available to users andnetwork administrators.Active Directory gives network users access to permitted resourcesanywhere on the network using a single logon process.It provides network administrators with an intuitive, hierarchical view of
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System Engineer - IT AdministrationUse Green Technologies and save the world.
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It provides network administrators with an intuitive, hierarchical view ofthe network and a single point of administration3for all network objects.
Ans: active directory is a domain controller which is use to authenticateand administrate the group of computer,user,server etc. remotely. all thepolicies and security will be applicable on the client machine which one isjoin the domain.and all this policies and security is defined in activedirectory.
1. What is LDAP?
Ans2: LDAP(light weight directory accerss protocol) is an internet protocolwhich Email and other services is used to look up information from theserver.
Q 4: Where is the AD database held? What other folders are relatedto AD?
The AD data base is store in NTDS.DIT.file
2. Can you connect Active Directory to other 3rd-party DirectoryServices? Name a few options.
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About Me - SystemAdministrator
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3. Where is the AD database held? What other folders are related toAD?
4. What is the SYSVOL folder?
The sysVOL folder stores the server’s copy of the domain’s public files.The contents such as group policy, users etc of the sysvol folder arereplicated to all domain controllers in the domain.
5. Name the AD NCs and replication issues for each NC
6. What are application partitions? When do I use them
7. How do you create a new application partition
8. How do you view replication properties for AD partitions and DCs?
9. What is the Global Catalog?
Ans.: Global Catalog is a server which maintains the information aboutmultiple domain with trust relationship agreement..
The global catalog is a distributed data repository that contains asearchable, partial representation of every object in every domain in amultidomain Active Directory forest. The global catalog is stored on domaincontrollers that have been designated as global catalog servers and isdistributed through multimaster replication. Searches that are directed tothe global catalog are faster because they do not involve referrals to
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the global catalog are faster because they do not involve referrals todifferent domain controllers.
10. How do you view all the GCs in the forest?
11. Why not make all DCs in a large forest as GCs?
12. Trying to look at the Schema, how can I do that?
13. What are the Support Tools? Why do I need them?
14. What is LDP? What is REPLMON? What is ADSIEDIT? What isNETDOM? What is REPADMIN?
15. What are sites? What are they used for?
16. What’s the difference between a site link’s schedule and interval?
17. What is the KCC?
Ans 18: KCC ( knowledge consistency checker ) is used to generatereplication topology for inter site replication and for intrasitereplication.with in a site replication traffic is done via remote procedurecalls over ip, while between site it is done through either RPC or SMTP.
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18. What is the ISTG? Who has that role by default?
19. What are the requirements for installing AD on a new server?
20. What can you do to promote a server to DC if you’re in a remotelocation with slow WAN link?
21. How can you forcibly remove AD from a server, and what do you dolater? • Can I get user passwords from the AD database?
22. What tool would I use to try to grab security related packets fromthe wire?
23. Name some OU design considerations.
24. What is tombstone lifetime attribute?
25. What do you do to install a new Windows 2003 DC in a Windows2000 AD?
26. What do you do to install a new Windows 2003 R2 DC in a Windows2003 AD?
27. How would you find all users that have not logged on since lastmonth?
28. What are the DS* commands?
29. What’s the difference between LDIFDE and CSVDE? Usageconsiderations?
30. What are the FSMO roles? Who has them by default? What happens
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30. What are the FSMO roles? Who has them by default? What happenswhen each one fails?
31. What FSMO placement considerations do you know of?
32. I want to look at the RID allocation table for a DC. What do I do?
33. What’s the difference between transferring a FSMO role and seizingone? Which one should you NOT seize? Why?
34. How do you configure a “stand-by operation master” for any of theroles?
35. How do you backup AD?
for taking backup of active directory you have to do this :first go to START -> PROGRAM ->ACCESORIES -> SYSTEM TOOLS ->BACKUPwhen the backup screen is flash then take the backup of SYSTEM STATEit will take the backup of all the necessary information about the systemincluding AD backup , DNS ETC.
36. How do you restore AD?
37. How do you change the DS Restore admin password?
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38. Why can’t you restore a DC that was backed up 4 months ago?
39. What are GPOs?
40. What is the order in which GPOs are applied?
41. Name a few benefits of using GPMC.
42. What are the GPC and the GPT? Where can I find them?
43. What are GPO links? What special things can I do to them?
44. What can I do to prevent inheritance from above?
45. How can I override blocking of inheritance?
46. How can you determine what GPO was and was not applied for auser? Name a few ways to do that.
47. A user claims he did not receive a GPO, yet his user and computeraccounts are in the right OU, and everyone else there gets the GPO.What will you look for?
48. Name a few differences in Vista GPOs
49. Name some GPO settings in the computer and user parts.
50. What are administrative templates?
51. What’s the difference between software publishing and assigning?
52. Can I deploy non-MSI software with GPO?
53. You want to standardize the desktop environments (wallpaper, MyDocuments, Start menu, printers etc.) on the computers in onedepartment. How would you do that?
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What is latest service pack Exchange 2003?
What is the name of Exchange Databases?
How many databases in Standard Exchange version ?
How many databases in Enterprise Exchange version ?
What is Storage Group?
What is mail store?
Explain Exchange transaction logs ?
Explain Exchange transaction logs ?
Why exchange is using transaction logs? Why not to write to data directly to theExchange database?
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How exchange database gets defragmented?
What is white space, and how can it be reclaimed?
What time online maintenance runs by default in Exchange?
What event log exchange logs after online defragmentation ?
What is white space, and how can it be reclaimed?
What is an IP address?
What is DNS? (what port)
What is DHCP? (what Port)
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IP address class range?
Private public IP range?
Public IP address range?
what is subnet mask, why it is important
What is Protocol?
Explain UDP
Explain TCP
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Explain TCP
How many ports available?
What’s new in Windows Server 2003 regarding the DNSmanagement? When DC promotion occurs with an existing forest, theActive Directory Installation Wizard contacts an existing DC to update thedirectory and replicate from the DC the required portions of the directory.If the wizard fails to locate a DC, it performs debugging and reports whatcaused the failure and how to fix the problem. In order to be located on anetwork, every DC must register in DNS DC locator DNS records. TheActive Directory Installation Wizard verifies a proper configuration of theDNS infrastructure. All DNS configuration debugging and reporting activityis done with the Active Directory Installation Wizard.
Question: What is the new kernel-mode driver for HTTP parsing and caching?
Ans: HTTP.SYS
Question: The act of allowing server applications to act as the user on the network is called:
Ans: Delegation
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Question: How can an IT administrator manage how a Terminal Server can be used, such asenforcing redirection capabilities, password access, and wallpaper settings?
Ans: Group Policy
Question: Windows Server 2003 contains the following patch management software:
Ans: Microsoft Software Update Services
Question: What is application pool?
Question: What is web service extension?
What’s new in Terminal Services for Windows 2003 Server?
Supports audio transmissions as well, although prepare for heavy network load.
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What’s new in Windows Server 2003 regarding the DNS management?
When DC promotion occurs with an existing forest, the Active Directory Installation Wizardcontacts an existing DC to update the directory and replicate from the DC the requiredportions of the directory. If the wizard fails to locate a DC, it performs debugging and reportswhat caused the failure and how to fix the problem. In order to be located on a network, everyDC must register in DNS DC locator DNS records. The Active Directory Installation Wizardverifies a proper configuration of the DNS infrastructure. All DNS configuration debuggingand reporting activity is done with the Active Directory Installation Wizard.
When should you create a forest?
Organizations that operate on radically different bases may require separate trees with distinctnamespaces. Unique trade or brand names often give rise to separate DNS identities.Organizations merge or are acquired and naming continuity is desired. Organizations formpartnerships and joint ventures. While access to common resources is desired, a separatelydefined tree can enforce more direct administrative and security restrictions.
How can you authenticate between forests?
Four types of authentication are used across forests:
1. Kerberos and NTLM network logon for remote access to a server in another forest;
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2. Kerberos and NTLM interactive logon for physical logon outside the user’s homeforest;
3. Kerberos delegation to N-tier application in another forest; and
4. User principal name (UPN) credentials.
What snap-in administrative tools are available for Active Directory?
Active Directory Domains and Trusts Manager, Active Directory Sites and ServicesManager, Active Directory Users and Group Manager, Active Directory Replication (optional,available from the Resource Kit), Active Directory Schema Manager (optional, available fromadminpak)
What do you do if earlier application doesn’t run on Windows Server 2003? When anapplication that ran on an earlier legacy version of Windows cannot be loaded during thesetup function or if it later malfunctions, you must run the compatibility mode function. Thisis accomplished by right-clicking the application or setup program and selecting Properties –>Compatibility –> selecting the previously supported operating system.
What snap-in administrative tools are available for Active Directory? Active DirectoryDomains and Trusts Manager, Active Directory Sites and Services Manager, ActiveDirectory Users and Group Manager, Active Directory Replication (optional, available fromthe Resource Kit), Active Directory Schema Manager (optional, available from adminpak)
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What types of classes exist in Windows Server 2003 Active Directory?
Structural class. The structural class is important to thesystem administrator in that it is the only type from which newActive Directory objects are created. Structural classes aredeveloped from either the modification of an existing structuraltype or the use of one or more abstract classes.
Abstract class. Abstract classes are so named because theytake the form of templates that actually create othertemplates (abstracts) and structural and auxiliary classes.Think of abstract classes as frameworks for the definingobjects.
Auxiliary class. The auxiliary class is a list of attributes.Rather than apply numerous attributes when creating astructural class, it provides a streamlined alternative byapplying a combination of attributes with a single includeaction.
88 class. The 88 class includes object classes defined prior to1993, when the 1988 X.500 specification was adopted. Thistype does not use the structural, abstract, and auxiliarydefinitions, nor is it in common use for the development ofobjects in Windows Server 2003 environments.
1. How do you delete a lingering object? Windows Server 2003provides a command called Repadmin that provides the ability todelete lingering objects in the Active Directory.
2. What is Global Catalog? The Global Catalog authenticates networkuser logons and fields inquiries about objects across a forest or tree.Every domain has at least one GC that is hosted on a domaincontroller. In Windows 2000, there was typically one GC on everysite in order to prevent user logon failures across the network.
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3. How is user account security established in Windows Server2003? When an account is created, it is given a unique accessnumber known as a security identifier (SID). Every group to whichthe user belongs has an associated SID. The user and related groupSIDs together form the user account’s security token, whichdetermines access levels to objects throughout the system andnetwork. SIDs from the security token are mapped to the accesscontrol list (ACL) of any object the user attempts to access.
4. If I delete a user and then create a new account with the sameusername and password, would the SID and permissions staythe same? No. If you delete a user account and attempt torecreate it with the same user name and password, the SID will bedifferent.
5. What do you do with secure sign-ons in an organization withmany roaming users? Credential Management feature of WindowsServer 2003 provides a consistent single sign-on experience forusers. This can be useful for roaming users who move betweencomputer systems. The Credential Management feature provides asecure store of user credentials that includes passwords and X.509certificates.
6. Anything special you should do when adding a user that has aMac? "Save password as encrypted clear text" must be selected onUser Properties Account Tab Options, since the Macs only storetheir passwords that way.
7. What remote access options does Windows Server 2003support? Dial-in, VPN, dial-in with callback.
8. Where are the documents and settings for the roaming profilestored? All the documents and environmental settings for theroaming user are stored locally on the system, and, when the userlogs off, all changes to the locally stored profile are copied to theshared server folder. Therefore, the first time a roaming user logs on
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shared server folder. Therefore, the first time a roaming user logs onto a new system the logon process may take some time, dependingon how large his profile folder is.
9. Where are the settings for all the users stored on a givenmachine? \Document and Settings\All Users
10. What languages can you use for log-on scripts? JavaScipt,VBScript, DOS batch files (.com, .bat, or even .exe)
What is a DNS resource record?
A resource record is an entry in a name server's database. There are severaltypes of resource records used, including name-to-address resolutioninformation. Resource records are maintained as ASCII files.
BOOTP helps a diskless workstation boot. How does it get a messageto the network looking for its IP address and the location of itsoperating system boot files
BOOTP sends a UDP message with a subnetwork broadcast address andwaits for a reply from a server that gives it the IP address. The samemessage might contain the name of the machine that has the boot files onit. If the boot image location is not specified, the workstation sendsanother UDP message to query the server.
What is the Network Time Protocol? Why is it used
The Network Time Protocol (NTP) is a protocol for synchronising the clocksof computer systems over packet-switched, variable-latency data
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of computer systems over packet-switched, variable-latency datanetworks. NTP uses UDP as its transport layer. It is designed particularlyto resist the effects of variable latency.
What is Virtual Memory?
Virtual memory is a technique that allows the execution of processes thatmay not be completely in memory. A separation of user logical memoryfrom physical memory allows an extremely large virtual memory to beprovided for programmers when only a smaller physical memory is available.It is commonly implemented by demand paging. A demand paging system issimilar to a paging system with swapping. Processes reside on secondarymemory (which is usually a disk). When we want to execute a process, weswap it into memory.
Describe how the DHCP lease is obtained. It’s a four-stepprocess consisting of (a) IP request, (b) IP offer, © IP selection and(d) acknowledgement.
I can’t seem to access the Internet, don’t have any access tothe corporate network and on ipconfig my address is169.254.*.*. What happened? The 169.254.*.* netmask isassigned to Windows machines running 98/2000/XP if the DHCPserver is not available. The name for the technology is APIPA(Automatic Private Internet Protocol Addressing).
We’ve installed a new Windows-based DHCP server, however,the users do not seem to be getting DHCP leases off of it. Theserver must be authorized first with the Active Directory.
How can you force the client to give up the dhcp lease if you
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How can you force the client to give up the dhcp lease if youhave access to the client PC? ipconfig /release
What authentication options do Windows 2000 Servers havefor remote clients? PAP, SPAP, CHAP, MS-CHAP and EAP.
What are the networking protocol options for the Windowsclients if for some reason you do not want to use TCP/IP?NWLink (Novell), NetBEUI, AppleTalk (Apple).
What is data link layer in the OSI reference model responsiblefor? Data link layer is located above the physical layer, butbelow the network layer. Taking raw data bits and packaging theminto frames. The network layer will be responsible for addressing theframes, while the physical layer is reponsible for retrieving andsending raw data bits.
What is binding order? The order by which the network protocolsare used for client-server communications. The most frequently usedprotocols should be at the top.
How do cryptography-based keys ensure the validity of datatransferred across the network? Each IP packet is assigned achecksum, so if the checksums do not match on both receiving andtransmitting ends, the data was modified or corrupted.
Should we deploy IPSEC-based security or certificate-basedsecurity? They are really two different technologies. IPSec securesthe TCP/IP communication and protects the integrity of the packets.Certificate-based security ensures the validity of authenticatedclients and servers.
What is LMHOSTS file? It’s a file stored on a host machine that isused to resolve NetBIOS to specific IP addresses.
What’s the difference between forward lookup and reverse
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What’s the difference between forward lookup and reverselookup in DNS? Forward lookup is name-to-address, the reverselookup is address-to-name.
How can you recover a file encrypted using EFS? Use the domainrecovery agent.
Microsoft software development engineer in test (SDET) interview questions
Chris Sells writes about the set of tester questions his friend got whenbeing interviewed for Software Development Engineer in Test position atMicrosoft Corp.
How would you deal with changes being made a week or so beforethe ship date?
How would you deal with a bug that no one wants to fix? Both theSDE and his lead have said they won’t fix it.
Write a function that counts the number of primes in the range [1-N]. Write the test cases for this function.
Given a MAKEFILE (yeah a makefile), design the data structure thata parser would create and then write code that iterates over thatdata structure executing commands if needed.
Write a function that inserts an integer into a linked list in ascendingorder. Write the test cases for this function.
Test the save dialog in Notepad. (This was the question I enjoyedthe most).
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Write the InStr function. Write the test cases for this function.
Write a function that will return the number of days in a month (notusing System.DateTime).
You have 3 jars. Each jar has a label on it: white, black, orwhite&black. You have 3 sets of marbles: white, black, andwhite&black. One set is stored in one jar. The labels on the jars areguaranteed to be incorrect (i.e. white will not contain white). Whichjar would you choose from to give you the best chances ofidentifying the which set of marbles in is in which jar.
Why do you want to work for Microsoft?
Write the test cases for a vending machine. (Those were thequestions I was asked. I had a lot of discussions about how tohandle situations. Such as a tester is focused on one part of anSDK. During triage it was determined that that portion of the SDKwas not on the critical path, and the tester was needed elsewhere.But the tester continued to test that portion because it is his baby.How would you get him to stop testing that portion and work onwhat needs to be worked on? Other situations came up likearranging tests into the different testing buckets (functional, stress,perf, etc.).)
Microsoft MSN interview questions
Aaron Boodman took up a job with Microsoft (MSN division) and told thestory of his interview in his Weblog. Below is an excerpt of questions
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story of his interview in his Weblog. Below is an excerpt of questionspotential candidates might find interesting.
Compare and contrast SQL Server with MySQL.
Compare and contrast stored procedures and dynamic SQL.
Describe a standard 3-tier architecture and the interfaces betweeneach tier.
Compare and contrast a rich client and browser-based webapplication
Compare and contrast WS and remoting protocols.
Design the data structures for the game battleship.
Consider the Dead Sea Scrolls. Imagine that you have these torn upold shreds of paper with ancient words on them. You want todevelop an application that will display one sheet at a time on thescreen. When the user left-clicks a word, the page containing theprevious occurence of that word is displayed and the word ishighlighted. When the user right-clicks a word, the page containingthe next occurence is displayed and the word is highlighted. Whenthe user double-clicks a word, the definition is displayed. How wouldyou design the application?
Given an array of the counties in NY represented as arrays of linesegments, find the collection of line segments which represent theoutline of the state.
Consider an SOA rich-client application used by several internationalvendors, where one vendor sees bandwidth usage far exceedingwhat would be expected based on their usage. What steps wouldyou follow to debug the problem?
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Imagine a trainyard. The purpose of a trainyard is to reorder trainsso that they are most efficiently grouped for outbound travel. Thebasic unit of a trainyard is a piece of track which looks like thefigure below. The train operator can perform three operations: movea car from the source to the spur, from the source to thedestination, or from the spur to the destination. So, for example, hecould reverse a train by moving each car onto the spur and thenmoving each car onto the destination. Write a function which, givenan array of integers representing the order of cars on the source,and another representing the order of cars desired on thedestination, prints instructions telling the trainyard operator whichoperations to perform to reorder the train correctly.
Implement a function which, given the integer value of the hoursand minutes hands of a clock, returns the measure of the degreesbetween them.
Find the lowest valued node in a Binary Search Tree (BST) greaterthan or equal to a a certain value.
Verify that a given BST is valid.
Given the following database table, which represents the history ofuser account statuses, give the query that returns the users whichhad a certain status on a certain day.
Implement the datastructures for a Tree and a function to populateit based off a page of text.
Explain hidden shares. Hidden or administrative shares are sharenames with a dollar sign ($) appended to their names. Administrativeshares are usually created automatically for the root of each drive letter.They do not display in the network browse list.
How do the permissions work in Windows 2000? What permissions
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How do the permissions work in Windows 2000? What permissionsdoes folder inherit from the parent? When you combine NTFSpermissions based on users and their group memberships, the leastrestrictive permissions take precedence. However, explicit Deny entriesalways override Allow entries.
Why can’t I encrypt a compressed file on Windows 2000? You caneither compress it or encrypt it, but not both.
If I rename an account, what must I do to make sure the renamedaccount has the same permissions as the original one? Nothing, it’sall maintained automatically.
What’s the most powerful group on a Windows system?Administrators.
What are the accessibility features in Windows 2000? StickyKeys,FilterKeys Narrator, Magnifier, and On-Screen Keyboard.
Why can’t I get to the Fax Service Management console? You canonly see it if a fax had been installed.
What do I need to ensure before deploying an application via aGroup Policy? Make sure it’s either an MSI file, or contains a ZAP file forGroup Policy.
How do you configure mandatory profiles? Rename ntuser.dat tontuser.man
I can’t get multiple displays to work in Windows 2000. Multipledisplays have to use peripheral connection interface (PCI) or AcceleratedGraphics Port (AGP) port devices to work properly with Windows 2000.
What’s a maximum number of processors Win2k supports? 2
I had some NTFS volumes under my Windows NT installation.
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I had some NTFS volumes under my Windows NT installation.What happened to NTFS after Win 2k installation? It got upgraded toNTFS 5.
How do you convert a drive from FAT/FAT32 to NTFS from thecommand line? convert c: /fs:ntfs
Explain APIPA. Auto Private IP Addressing (APIPA) takes effect onWindows 2000 Professional computers if no DHCP server can becontacted. APIPA assigns the computer an IP address within the range of169.254.0.0 through 169.254.255.254 with a subnet mask of 255.255.0.0.
How does Internet Connection Sharing work on Windows 2000?Internet Connection Sharing (ICS) uses the DHCP Allocator service toassign dynamic IP addresses to clients on the LAN within the range of192.168.0.2 through 192.168.0.254. In addition, the DNS Proxy servicebecomes enabled when youimplement ICS.
What is presentation layer responsible for in the OSI model? Thepresentation layer establishes the data format prior to passing it along tothe network application’s interface. TCP/IP networks perform this task atthe application layer.
Does Windows Server 2003 support IPv6? Yes, run ipv6.exe fromcommand line to disable it.
Can Windows Server 2003 function as a bridge? Yes, and it’s a newfeature for the 2003 product. You can combine several networks anddevices connected via several adapters by enabling IP routing.
What’s the difference between the basic disk and dynamic disk?The basic type contains partitions, extended partitions, logical drivers, andan assortment of static volumes; the dynamic type does not use partitions
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an assortment of static volumes; the dynamic type does not use partitionsbut dynamically manages volumes and provides advanced storage options
What’s a media pool? It is any compilation of disks or tapes with thesame administrative properties.
How do you install recovery console? C:\i386\win32 /cmdcons,assuming that your Win server installation is on drive C.
What’s new in Terminal Services for Windows 2003 Server?Supports audio transmissions as well, although prepare for heavy networkload.
What scripts ship with IIS 6.0? iisweb.vsb to create, delete, start,stop, and list Web sites, iisftp.vsb to create, delete, start, stop, and listFTP sites, iisdir.vsb to create, delete, start, stop, and display virtualdirectories, iisftpdr.vsb to create, delete, start, stop, and display virtualdirectories under an FTP root, iiscnfg.vbs to export and import IISconfiguration to an XML file.
What’s the name of the user who connects to the Web siteanonymously? IUSR_computername
What secure authentication and encryption mechanisms aresupported by IIS 6.0? Basic authentication, Digest authentication,Advanced digest authentication, Certificate-based Web transactions thatuse PKCS #7/PKCS #10, Fortezza, SSL, Server-Gated Cryptography,Transport Layer Security
What’s the relation between SSL and TLS? Transport Layer Security(TLS) extends SSL by providing cryptographic authentication.
What’s the role of http.sys in IIS? It is the point of contact for allincoming HTTP requests. It listens for requests and queues them until theyare all processed, no more queues are available, or the Web server is shutdown.
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Where’s ASP cache located on IIS 6.0? On disk, as opposed tomemory, as it used to be in IIS 5.
What is socket pooling? Non-blocking socket usage, introduced in IIS6.0. More than one application can use a given socket.
Describe the process of clustering with Windows 2003 Server whena new node is added. As a node goes online, it searches for other nodesto join by polling the designated internal network. In this way, all nodes arenotified of the new node’s existence. If other nodes cannot be found on apreexisting cluster, the new node takes control of the quorum resourcesresiding on the shared disk that contains state and configuration data.
What applications are not capable of performing in Windows 2003Server clusters? The ones written exclusively for NetBEUI and IPX.
What’s a heartbeat? Communication processes between the nodesdesigned to ensure node’s health.
What’s a threshold in clustered environment? The number of timesa restart is attempted, when the node fails.
You need to change and admin password on a clustered Windowsbox, but that requires rebooting the cluster, doesn’t it? No, it doesn’t.In 2003 environment you can do that via cluster.exe utility which does notrequire rebooting the entire cluster.
For the document of size 1 MB, what size would you expect theindex to be with Indexing Service? 150-300 KB, 15-30% is a reasonableexpectation.
Doesn’t the Indexing Service introduce a security flaw whenallowing access to the index? No, because users can only view theindices of documents and folders that they have permissions for.
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What’s the typical size of the index? Less then 100K documents - upto 128 MB. More than that - 256+ MB.
Which characters should be enclosed in quotes when searchingthe index? &, @, $, #, ^, ( ), and |.
How would you search for C++? Just enter C++, since + is not aspecial character (and neither is C).
What about Barnes&Noble? Should be searched for asBarnes’&’Noble.
Are the searches case-sensitive? No.
What’s the order of precedence of Boolean operators in MicrosoftWindows 2003 Server Indexing Service? NOT, AND, NEAR, OR.
What’s a vector space query? A multiple-word query where theweight can be assigned to each of the search words. For example, if youwant to fight information on ‘black hole’, but would prefer to give moreweight to the word hole, you can enter black[1] hole[20] into the searchwindow.
What’s a response queue? It’s the message queue that holdsresponse messages sent from the receiving application to the sender.
What’s MQPing used for? Testing Microsoft Message Queue servicesbetween the nodes on a network.
Which add-on package for Windows 2003 Server would you use tomonitor the installed software and license compliance? SMS (SystemManagement Server).
Which service do you use to set up various alerts? MOM (MicrosoftOperations Manager).
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What languages does Windows Scripting Host support? VB,VBScript, Jscript
Windows Server 2003 interview and certification questions
54. How do you double-boot a Win 2003 server box? The Boot.inifile is set as read-only, system, and hidden to prevent unwantedediting. To change the Boot.ini timeout and default settings, use theSystem option in Control Panel from the Advanced tab and selectStartup.
55. What do you do if earlier application doesn’t run on WindowsServer 2003? When an application that ran on an earlier legacyversion of Windows cannot be loaded during the setup function or ifit later malfunctions, you must run the compatibility mode function.This is accomplished by right-clicking the application or setupprogram and selecting Properties –> Compatibility –> selecting thepreviously supported operating system.
56. If you uninstall Windows Server 2003, which operatingsystems can you revert to? Win ME and Win 98.
57. How do you get to Internet Firewall settings? Start –> ControlPanel –> Network and Internet Connections –> NetworkConnections.
58. What are the Windows Server 2003 keyboard shortcuts?Winkey opens or closes the Start menu. Winkey + BREAK displaysthe System Properties dialog box. Winkey + TAB moves the focus tothe next application in the taskbar. Winkey + SHIFT + TAB moves
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the next application in the taskbar. Winkey + SHIFT + TAB movesthe focus to the previous application in the taskbar. Winkey + Bmoves the focus to the notification area. Winkey + D shows thedesktop. Winkey + E opens Windows Explorer showing My Computer.Winkey + F opens the Search panel. Winkey + CTRL + F opens theSearch panel with Search for Computers module selected. Winkey +F1 opens Help. Winkey + M minimizes all. Winkey + SHIFT+ M undoesminimization. Winkey + R opens Run dialog. Winkey + U opens theUtility Manager. Winkey + L locks the computer.
59. What is Active Directory? Active Directory is a network-basedobject store and service that locates and manages resources, andmakes these resources available to authorized users and groups. Anunderlying principle of the Active Directory is that everything isconsidered an object—people, servers, workstations, printers,documents, and devices. Each object has certain attributes and itsown security access control list (ACL).
60. Where are the Windows NT Primary Domain Controller (PDC)and its Backup Domain Controller (BDC) in Server 2003? TheActive Directory replaces them. Now all domain controllers share amultimaster peer-to-peer read and write relationship that hostscopies of the Active Directory.
61. How long does it take for security changes to be replicatedamong the domain controllers? Security-related modifications arereplicated within a site immediately. These changes include accountand individual user lockout policies, changes to password policies,changes to computer account passwords, and modifications to theLocal Security Authority (LSA).
62. What’s new in Windows Server 2003 regarding the DNSmanagement? When DC promotion occurs with an existing forest,the Active Directory Installation Wizard contacts an existing DC toupdate the directory and replicate from the DC the required portionsof the directory. If the wizard fails to locate a DC, it performs
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of the directory. If the wizard fails to locate a DC, it performsdebugging and reports what caused the failure and how to fix theproblem. In order to be located on a network, every DC mustregister in DNS DC locator DNS records. The Active DirectoryInstallation Wizard verifies a proper configuration of the DNSinfrastructure. All DNS configuration debugging and reporting activityis done with the Active Directory Installation Wizard.
63. When should you create a forest? Organizations that operate onradically different bases may require separate trees with distinctnamespaces. Unique trade or brand names often give rise toseparate DNS identities. Organizations merge or are acquired andnaming continuity is desired. Organizations form partnerships andjoint ventures. While access to common resources is desired, aseparately defined tree can enforce more direct administrative andsecurity restrictions.
64. How can you authenticate between forests? Four types ofauthentication are used across forests: (1) Kerberos and NTLMnetwork logon for remote access to a server in another forest; (2)Kerberos and NTLM interactive logon for physical logon outside theuser’s home forest; (3) Kerberos delegation to N-tier application inanother forest; and (4) user principal name (UPN) credentials.
65. What snap-in administrative tools are available for ActiveDirectory? Active Directory Domains and Trusts Manager, ActiveDirectory Sites and Services Manager, Active Directory Users andGroup Manager, Active Directory Replication (optional, available fromthe Resource Kit), Active Directory Schema Manager (optional,available from adminpak)
66. What types of classes exist in Windows Server 2003 ActiveDirectory?
1. Structural class. The structural class is important to thesystem administrator in that it is the only type from which new
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system administrator in that it is the only type from which newActive Directory objects are created. Structural classes aredeveloped from either the modification of an existing structuraltype or the use of one or more abstract classes.
2. Abstract class. Abstract classes are so named because theytake the form of templates that actually create othertemplates (abstracts) and structural and auxiliary classes.Think of abstract classes as frameworks for the definingobjects.
3. Auxiliary class. The auxiliary class is a list of attributes.Rather than apply numerous attributes when creating astructural class, it provides a streamlined alternative byapplying a combination of attributes with a single includeaction.
4. 88 class. The 88 class includes object classes defined prior to1993, when the 1988 X.500 specification was adopted. Thistype does not use the structural, abstract, and auxiliarydefinitions, nor is it in common use for the development ofobjects in Windows Server 2003 environments.
67. How do you delete a lingering object? Windows Server 2003provides a command called Repadmin that provides the ability todelete lingering objects in the Active Directory.
68. What is Global Catalog? The Global Catalog authenticates networkuser logons and fields inquiries about objects across a forest or tree.Every domain has at least one GC that is hosted on a domaincontroller. In Windows 2000, there was typically one GC on everysite in order to prevent user logon failures across the network.
69. How is user account security established in Windows Server2003? When an account is created, it is given a unique accessnumber known as a security identifier (SID). Every group to whichthe user belongs has an associated SID. The user and related group
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the user belongs has an associated SID. The user and related groupSIDs together form the user account’s security token, whichdetermines access levels to objects throughout the system andnetwork. SIDs from the security token are mapped to the accesscontrol list (ACL) of any object the user attempts to access.
70. If I delete a user and then create a new account with the sameusername and password, would the SID and permissions staythe same? No. If you delete a user account and attempt torecreate it with the same user name and password, the SID will bedifferent.
71. What do you do with secure sign-ons in an organization withmany roaming users? Credential Management feature of WindowsServer 2003 provides a consistent single sign-on experience forusers. This can be useful for roaming users who move betweencomputer systems. The Credential Management feature provides asecure store of user credentials that includes passwords and X.509certificates.
72. Anything special you should do when adding a user that has aMac? "Save password as encrypted clear text" must be selected onUser Properties Account Tab Options, since the Macs only storetheir passwords that way.
73. What remote access options does Windows Server 2003support? Dial-in, VPN, dial-in with callback.
74. Where are the documents and settings for the roaming profilestored? All the documents andenvironmental settings for the roaming user are stored locally on thesystem, and, when the user logs off, all changes to the locallystored profile are copied to the shared server folder. Therefore, thefirst time a roaming user logs on to a new system the logon processmay take some time, depending on how large his profile folder is.
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75. Where are the settings for all the users stored on a givenmachine? \Document and Settings\All Users
76. What languages can you use for log-on scripts? JavaScipt,VBScript, DOS batch files (.com, .bat, or
50. What's the difference between software publishing and assigning
New Active Directory features in Windows Server 2003 with sp1 :
1. Multiple selection of user objects.
2. Drag-and-drop functionality
3. Efficient search capabilities
4. Saved queries.
5. Active Directory command-line tools
6. InetOrgPerson class.
7. Application directory partitions.
8. Universal group membership caching.
9. Secure LDAP traffic.
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10.Active Directory quotas.
New domain- and forest-wide Active Directory features :
1. Domain controller rename tool.
2. Different location option for user and computer accounts.
3. Domain rename.
4. Forest trusts.
5. Forest restructuring.
6. Defunct schema objects.
7. Dynamic auxiliary classes.
8. Global catalog replication improvements.
9. Replication enhancements.
10. User access control to resources between domains or forests.
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Req to install win 2003 Domain
Requirement to install the Win 2003 Domain Conroller :
1. An NTFS partition with enough free space.
2. An Administrator's username and password.
3. The correct operating system version.
4. A NIC Properly configured TCP/IP (IP address, subnet maskand - optional - default gateway).
5. A network connection (to a hub or to another computer via a crossovercable).
6. An operational DNS server (which can be installed on the DC itself).
7. A Domain name that you want to useThe Windows Server 2003 CD media (or at least the i386 folder).
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Network Security
Home Network SecurityThis document gives home users an overview of the security risks and countermeasures associated with Internet connectivity, especially inthe context of “always-on” or broadband access services (such as cable modems and DSL). However, much of the content is also relevantto traditional dial-up users (users who connect to the Internet using a modem). IntroductionComputer securityWhat is computer security?Why should I care about computer security?Who would want to break into my computer at home?How easy is it to break into my computer?TechnologyWhat does "broadband" mean?What is cable modem access?What is DSL access?How are broadband services different from traditional dial-up services?How is broadband access different from the network I use at work?What is a protocol?What is IP?What is an IP address?What are static and dynamic addressing?What is NAT?What are TCP and UDP ports?What is a firewall?What does antivirus software do?Computer security risks to home users What is at risk?Intentional misuse of your computerTrojan horse programsBack door and remote administration programsDenial of serviceBeing an intermediary for another attack
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Unprotected Windows sharesMobile code (Java, JavaScript, and ActiveX)Cross-site scriptingEmail spoofingEmail-borne virusesHidden file extensionsChat clientsPacket sniffingAccidents and other risksDisk failurePower failure and surgesPhysical theftActions home users can take to protect their computer systemsConsult your system support personnel if you work from homeUse virus protection softwareUse a firewallDon’t open unknown email attachmentsDon’t run programs of unknown originDisable hidden filename extensionsKeep all applications (including your operating system) patchedTurn off your computer or disconnect from the network when not in useDisable Java, JavaScript, and ActiveX if possibleDisable scripting features in email programsMake regular backups of critical dataMake a boot disk in case your computer is damaged or compromisedAppendix: References and additional informationDocument Revision HistoryI. Computer securityA. What is computer security?Computer security is the process of preventing and detecting unauthorized use of your computer. Prevention measures help you to stopunauthorized users (also known as "intruders") from accessing any part of your computer system. Detection helps you to determinewhether or not someone attempted to break into your system, if they were successful, and what they may have done.B. Why should I care about computer security?We use computers for everything from banking and investing to shopping and communicating with others through email or chat programs.Although you may not consider your communications "top secret," you probably do not want strangers reading your email, using your
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computer to attack other systems, sending forged email from your computer, or examining personal information stored on your computer(such as financial statements).C. Who would want to break into my computer at home?Intruders (also referred to as hackers, attackers, or crackers) may not care about your identity. Often they want to gain control of yourcomputer so they can use it to launch attacks on other computer systems.Having control of your computer gives them the ability to hide their true location as they launch attacks, often against high-profile computersystems such as government or financial systems. Even if you have a computer connected to the Internet only to play the latest games orto send email to friends and family, your computer may be a target.Intruders may be able to watch all your actions on the computer, or cause damage to your computer by reformatting your hard drive orchanging your data.D. How easy is it to break into my computer?Unfortunately, intruders are always discovering new vulnerabilities (informally called "holes") to exploit in computer software. Thecomplexity of software makes it increasingly difficult to thoroughly test the security of computer systems.When holes are discovered, computer vendors will usually develop patches to address the problem(s). However, it is up to you, the user, toobtain and install the patches, or correctly configure the software to operate more securely. Most of the incident reports of computer break-ins received at the CERT/CC could have been prevented if system administrators and users kept their computers up-to-date with patchesand security fixes.Also, some software applications have default settings that allow other users to access your computer unless you change the settings to bemore secure. Examples include chat programs that let outsiders execute commands on your computer or web browsers that could allowsomeone to place harmful programs on your computer that run when you click on them.II. TechnologyThis section provides a basic introduction to the technologies that underlie the Internet. It was written with the novice end-user in mind andis not intended to be a comprehensive survey of all Internet-based technologies. Subsections provide a short overview of each topic. Thissection is a basic primer on the relevant technologies. For those who desire a deeper understanding of the concepts covered here, weinclude links to additional information.A. What does broadband mean?"Broadband" is the general term used to refer to high-speed network connections. In this context, Internet connections via cable modemand Digital Subscriber Line (DSL) are frequently referred to as broadband Internet connections. "Bandwidth" is the term used to describethe relative speed of a network connection -- for example, most current dial-up modems can support a bandwidth of 56 kbps (thousand bitsper second). There is no set bandwidth threshold required for a connection to be referred to as "broadband", but it is typical for connectionsin excess of 1 Megabit per second (Mbps) to be so named.B. What is cable modem access?A cable modem allows a single computer (or network of computers) to connect to the Internet via the cable TV network. The cable modemusually has an Ethernet LAN (Local Area Network) connection to the computer, and is capable of speeds in excess of 5 Mbps.Typical speeds tend to be lower than the maximum, however, since cable providers turn entire neighborhoods into LANs which share the
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same bandwidth. Because of this "shared-medium" topology, cable modem users may experience somewhat slower network access duringperiods of peak demand, and may be more susceptible to risks such as packet sniffing and unprotected windows shares than users withother types of connectivity. (See the "Computer security risks to home users" section of this document.)C. What is DSL access?Digital Subscriber Line (DSL) Internet connectivity, unlike cable modem-based service, provides the user with dedicated bandwidth.However, the maximum bandwidth available to DSL users is usually lower than the maximum cable modem rate because of differences intheir respective network technologies. Also, the "dedicated bandwidth" is only dedicated between your home and the DSL provider's centraloffice -- the providers offer little or no guarantee of bandwidth all the way across the Internet.DSL access is not as susceptible to packet sniffing as cable modem access, but many of the other security risks we'll cover apply to bothDSL and cable modem access. (See the "Computer security risks to home users" section of this document.)D. How are broadband services different from traditional dial-up services?Traditional dial-up Internet services are sometimes referred to as "dial-on-demand" services. That is, your computer only connects to theInternet when it has something to send, such as email or a request to load a web page. Once there is no more data to be sent, or after acertain amount of idle time, the computer disconnects the call. Also, in most cases each call connects to a pool of modems at the ISP, andsince the modem IP addresses are dynamically assigned, your computer is usually assigned a different IP address on each call. As a result,it is more difficult (not impossible, just difficult) for an attacker to take advantage of vulnerable network services to take control of yourcomputer.Broadband services are referred to as "always-on" services because there is no call setup when your computer has something to send. Thecomputer is always on the network, ready to send or receive data through its network interface card (NIC). Since the connection is alwaysup, your computer’s IP address will change less frequently (if at all), thus making it more of a fixed target for attack.What’s more, many broadband service providers use well-known IP addresses for home users. So while an attacker may not be able tosingle out your specific computer as belonging to you, they may at least be able to know that your service providers’ broadband customersare within a certain address range, thereby making your computer a more likely target than it might have been otherwise.The table below shows a brief comparison of traditional dial-up and broadband services.
Dial-upBroadbandConnection typeDial on demandAlways onIP addressChanges on each callStatic or infrequently changingRelative connection speed
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LowHighRemote control potentialComputer must be dialed in to control remotelyComputer is always connected, so remote control can occur anytimeISP-provided securityLittle or noneLittle or noneTable 1: Comparison of Dial-up and Broadband Services
E. How is broadband access different from the network I use at work?Corporate and government networks are typically protected by many layers of security, ranging from network firewalls to encryption. Inaddition, they usually have support staff who maintain the security and availability of these network connections.Although your ISP is responsible for maintaining the services they provide to you, you probably won’t have dedicated staff on hand tomanage and operate your home network. You are ultimately responsible for your own computers. As a result, it is up to you to takereasonable precautions to secure your computers from accidental or intentional misuse.F. What is a protocol?A protocol is a well-defined specification that allows computers to communicate across a network. In a way, protocols define the "grammar"that computers can use to "talk" to each other.G. What is IP?IP stands for "Internet Protocol". It can be thought of as the common language of computers on the Internet. There are a number ofdetailed descriptions of IP given elsewhere, so we won't cover it in detail in this document. However, it is important to know a few thingsabout IP in order to understand how to secure your computer. Here we’ll cover IP addresses, static vs. dynamic addressing, NAT, and TCPand UDP Ports.An overview of TCP/IP can be found in the TCP/IP Frequently Asked Questions (FAQ) athttp://www.faqs.org/faqs/internet/tcp-ip/tcp-ip-faq/part1/andhttp://www.faqs.org/faqs/internet/tcp-ip/tcp-ip-faq/part2/H. What is an IP address?IP addresses are analogous to telephone numbers – when you want to call someone on the telephone, you must first know their telephonenumber. Similarly, when a computer on the Internet needs to send data to another computer, it must first know its IP address. IP addressesare typically shown as four numbers separated by decimal points, or “dots”. For example, 10.24.254.3 and 192.168.62.231 are IPaddresses.If you need to make a telephone call but you only know the person’s name, you can look them up in the telephone directory (or calldirectory services) to get their telephone number. On the Internet, that directory is called the Domain Name System, or DNS for short. If
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you know the name of a server, say www.cert.org, and you type this into your web browser, your computer will then go ask its DNS serverwhat the numeric IP address is that is associated with that name.Every computer on the Internet has an IP address associated with it that uniquely identifies it. However, that address may change overtime, especially if the computer isdialing into an Internet Service Provider (ISP)connected behind a network firewallconnected to a broadband service using dynamic IP addressing.I. What are static and dynamic addressing?Static IP addressing occurs when an ISP permanently assigns one or more IP addresses for each user. These addresses do not changeover time. However, if a static address is assigned but not in use, it is effectively wasted. Since ISPs have a limited number of addressesallocated to them, they sometimes need to make more efficient use of their addresses.Dynamic IP addressing allows the ISP to efficiently utilize their address space. Using dynamic IP addressing, the IP addresses of individualuser computers may change over time. If a dynamic address is not in use, it can be automatically reassigned to another computer asneeded.J. What is NAT?Network Address Translation (NAT) provides a way to hide the IP addresses of a private network from the Internet while still allowingcomputers on that network to access the Internet. NAT can be used in many different ways, but one method frequently used by home usersis called "masquerading".Using NAT masquerading, one or more devices on a LAN can be made to appear as a single IP address to the outside Internet. This allowsfor multiple computers in a home network to use a single cable modem or DSL connection without requiring the ISP to provide more thanone IP address to the user. Using this method, the ISP-assigned IP address can be either static or dynamic. Most network firewalls supportNAT masquerading.K. What are TCP and UDP Ports?TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) are both protocols that use IP. Whereas IP allows two computers totalk to each other across the Internet, TCP and UDP allow individual applications (also known as "services") on those computers to talk toeach other.In the same way that a telephone number or physical mail box might be associated with more than one person, a computer might havemultiple applications (e.g. email, file services, web services) running on the same IP address. Ports allow a computer to differentiateservices such as email data from web data. A port is simply a number associated with each application that uniquely identifies that serviceon that computer. Both TCP and UDP use ports to identify services. Some common port numbers are 80 for web (HTTP), 25 for email(SMTP), and 53 for Domain Name System (DNS).L. What is a firewall?The Firewalls FAQ (http://www.faqs.org/faqs/firewalls-faq/) defines a firewall as "a system or group of systems that enforces an accesscontrol policy between two networks." In the context of home networks, a firewall typically takes one of two forms:Software firewall - specialized software running on an individual computer, or
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Network firewall - a dedicated device designed to protect one or more computers.Both types of firewall allow the user to define access policies for inbound connections to the computers they are protecting. Many alsoprovide the ability to control what services (ports) the protected computers are able to access on the Internet (outbound access). Mostfirewalls intended for home use come with pre-configured security policies from which the user chooses, and some allow the user tocustomize these policies for their specific needs.More information on firewalls can be found in the Additional resources section of this document.M. What does antivirus software do?There are a variety of antivirus software packages that operate in many different ways, depending on how the vendor chose to implementtheir software. What they have in common, though, is that they all look for patterns in the files or memory of your computer that indicatethe possible presence of a known virus. Antivirus packages know what to look for through the use of virus profiles (sometimes called"signatures") provided by the vendor.New viruses are discovered daily. The effectiveness of antivirus software is dependent on having the latest virus profiles installed on yourcomputer so that it can look for recently discovered viruses. It is important to keep these profiles up to date.More information about viruses and antivirus software can be found on the CERT Computer Virus Resource pagehttp://www.cert.org/other_sources/viruses.htmlIII. Computer security risks to home usersA. What is at risk?Information security is concerned with three main areas:Confidentiality - information should be available only to those who rightfully have access to itIntegrity -- information should be modified only by those who are authorized to do soAvailability -- information should be accessible to those who need it when they need itThese concepts apply to home Internet users just as much as they would to any corporate or government network. You probably wouldn'tlet a stranger look through your important documents. In the same way, you may want to keep the tasks you perform on your computerconfidential, whether it's tracking your investments or sending email messages to family and friends. Also, you should have someassurance that the information you enter into your computer remains intact and is available when you need it.Some security risks arise from the possibility of intentional misuse of your computer by intruders via the Internet. Others are risks that youwould face even if you weren't connected to the Internet (e.g. hard disk failures, theft, power outages). The bad news is that you probablycannot plan for every possible risk. The good news is that you can take some simple steps to reduce the chance that you'll be affected bythe most common threats -- and some of those steps help with both the intentional and accidental risks you're likely to face.Before we get to what you can do to protect your computer or home network, let’s take a closer look at some of these risks.B. Intentional misuse of your computerThe most common methods used by intruders to gain control of home computers are briefly described below. More detailed information isavailable by reviewing the URLs listed in the References section below.Trojan horse programsBack door and remote administration programs
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Denial of serviceBeing an intermediary for another attackUnprotected Windows sharesMobile code (Java, JavaScript, and ActiveX)Cross-site scriptingEmail spoofingEmail-borne virusesHidden file extensionsChat clientsPacket sniffing13. Trojan horse programsTrojan horse programs are a common way for intruders to trick you (sometimes referred to as "social engineering") into installing "backdoor" programs. These can allow intruders easy access to your computer without your knowledge, change your system configurations, orinfect your computer with a computer virus. More information about Trojan horses can be found in the following document.http://www.cert.org/advisories/CA-1999-02.html14. Back door and remote administration programsOn Windows computers, three tools commonly used by intruders to gain remote access to your computer are BackOrifice, Netbus, andSubSeven. These back door or remote administration programs, once installed, allow other people to access and control your computer. Werecommend that you review the CERT vulnerability note about Back Orifice. This document describes how it works, how to detect it, andhow to protect your computers from it:http://www.cert.org/vul_notes/VN-98.07.backorifice.html15. Denial of serviceAnother form of attack is called a denial-of-service (DoS) attack. This type of attack causes your computer to crash or to become so busyprocessing data that you are unable to use it. In most cases, the latest patches will prevent the attack. The following documents describedenial-of-service attacks in greater detail.http://www.cert.org/advisories/CA-2000-01.htmlhttp://www.cert.org/archive/pdf/DoS_trends.pdfIt is important to note that in addition to being the target of a DoS attack, it is possible for your computer to be used as a participant in adenial-of-service attack on another system.16. Being an intermediary for another attackIntruders will frequently use compromised computers as launching pads for attacking other systems. An example of this is how distributeddenial-of-service (DDoS) tools are used. The intruders install an "agent" (frequently through a Trojan horse program) that runs on thecompromised computer awaiting further instructions. Then, when a number of agents are running on different computers, a single "handler"can instruct all of them to launch a denial-of-service attack on another system. Thus, the end target of the attack is not your own computer,but someone else’s -- your computer is just a convenient tool in a larger attack.
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17. Unprotected Windows sharesUnprotected Windows networking shares can be exploited by intruders in an automated way to place tools on large numbers of Windows-based computers attached to the Internet. Because site security on the Internet is interdependent, a compromised computer not onlycreates problems for the computer's owner, but it is also a threat to other sites on the Internet. The greater immediate risk to the Internetcommunity is the potentially large number of computers attached to the Internet with unprotected Windows networking shares combinedwith distributed attack tools such as those described inhttp://www.cert.org/incident_notes/IN-2000-01.htmlAnother threat includes malicious and destructive code, such as viruses or worms, which leverage unprotected Windows networking sharesto propagate. One such example is the 911 worm described inhttp://www.cert.org/incident_notes/IN-2000-03.htmlThere is great potential for the emergence of other intruder tools that leverage unprotected Windows networking shares on a widespreadbasis.18. Mobile code (Java/JavaScript/ActiveX)There have been reports of problems with "mobile code" (e.g. Java, JavaScript, and ActiveX). These are programming languages that letweb developers write code that is executed by your web browser. Although the code is generally useful, it can be used by intruders togather information (such as which web sites you visit) or to run malicious code on your computer. It is possible to disable Java, JavaScript,and ActiveX in your web browser. We recommend that you do so if you are browsing web sites that you are not familiar with or do not trust.Also be aware of the risks involved in the use of mobile code within email programs. Many email programs use the same code as webbrowsers to display HTML. Thus, vulnerabilities that affect Java, JavaScript, and ActiveX are often applicable to email as well as web pages.More information on malicious code is available in http://www.cert.org/tech_tips/malicious_code_FAQ.htmlMore information on ActiveX security is available in http://www.cert.org/archive/pdf/activeX_report.pdf19. Cross-site scriptingA malicious web developer may attach a script to something sent to a web site, such as a URL, an element in a form, or a database inquiry.Later, when the web site responds to you, the malicious script is transferred to your browser.You can potentially expose your web browser to malicious scripts byfollowing links in web pages, email messages, or newsgroup postings without knowing what they link tousing interactive forms on an untrustworthy siteviewing online discussion groups, forums, or other dynamically generated pages where users can post text containing HTML tagsMore information regarding the risks posed by malicious code in web links can be found in CA-2000-02 Malicious HTML Tags Embedded inClient Web Requests.20. Email spoofingEmail “spoofing” is when an email message appears to have originated from one source when it actually was sent from another source.Email spoofing is often an attempt to trick the user into making a damaging statement or releasing sensitive information (such aspasswords).Spoofed email can range from harmless pranks to social engineering ploys. Examples of the latter include
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email claiming to be from a system administrator requesting users to change their passwords to a specified string and threatening tosuspend their account if they do not complyemail claiming to be from a person in authority requesting users to send them a copy of a password file or other sensitive informationNote that while service providers may occasionally request that you change your password, they usually will not specify what you shouldchange it to. Also, most legitimate service providers would never ask you to send them any password information via email. If you suspectthat you may have received a spoofed email from someone with malicious intent, you should contact your service provider's supportpersonnel immediately.21. Email borne virusesViruses and other types of malicious code are often spread as attachments to email messages. Before opening any attachments, be sureyou know the source of the attachment. It is not enough that the mail originated from an address you recognize. The Melissa virus (seeReferences) spread precisely because it originated from a familiar address. Also, malicious code might be distributed in amusing or enticingprograms.Many recent viruses use these social engineering techniques to spread. Examples includeW32/Sircam -- http://www.cert.org/advisories/CA-2001-22.html W32/Goner -- http://www.cert.org/incident_notes/IN-2001-15.html Never run a program unless you know it to be authored by a person or company that you trust. Also, don't send programs of unknownorigin to your friends or coworkers simply because they are amusing -- they might contain a Trojan horse program.22. Hidden file extensionsWindows operating systems contain an option to "Hide file extensions for known file types". The option is enabled by default, but a user maychoose to disable this option in order to have file extensions displayed by Windows. Multiple email-borne viruses are known to exploithidden file extensions. The first major attack that took advantage of a hidden file extension was the VBS/LoveLetter worm which containedan email attachment named "LOVE-LETTER-FOR-YOU.TXT.vbs". Other malicious programs have since incorporated similar naming schemes.Examples includeDownloader (MySis.avi.exe or QuickFlick.mpg.exe)VBS/Timofonica (TIMOFONICA.TXT.vbs)VBS/CoolNote (COOL_NOTEPAD_DEMO.TXT.vbs)VBS/OnTheFly (AnnaKournikova.jpg.vbs)The files attached to the email messages sent by these viruses may appear to be harmless text (.txt), MPEG (.mpg), AVI (.avi) or other filetypes when in fact the file is a malicious script or executable (.vbs or .exe, for example). For further information about these and otherviruses, please visit the sites listed on our Computer Virus Resource page:http://www.cert.org/other_sources/viruses.html23. Chat clientsInternet chat applications, such as instant messaging applications and Internet Relay Chat (IRC) networks, provide a mechanism forinformation to be transmitted bi-directionally between computers on the Internet. Chat clients provide groups of individuals with the meansto exchange dialog, web URLs, and in many cases, files of any type.
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Because many chat clients allow for the exchange of executable code, they present risks similar to those of email clients. As with emailclients, care should be taken to limit the chat client’s ability to execute downloaded files. As always, you should be wary of exchanging fileswith unknown parties.24. Packet sniffingA packet sniffer is a program that captures data from information packets as they travel over the network. That data may include usernames, passwords, and proprietary information that travels over the network in clear text. With perhaps hundreds or thousands ofpasswords captured by the packet sniffer, intruders can launch widespread attacks on systems. Installing a packet sniffer does notnecessarily require administrator-level access.Relative to DSL and traditional dial-up users, cable modem users have a higher risk of exposure to packet sniffers since entireneighborhoods of cable modem users are effectively part of the same LAN. A packet sniffer installed on any cable modem user's computerin a neighborhood may be able to capture data transmitted by any other cable modem in the same neighborhood.C. Accidents and other risksIn addition to the risks associated with connecting your computer to the Internet, there are a number of risks that apply even if thecomputer has no network connections at all. Most of these risks are well-known, so we won’t go into much detail in this document, but it isimportant to note that the common practices associated with reducing these risks may also help reduce susceptibility to the network-basedrisks discussed above.0. Disk failureRecall that availability is one of the three key elements of information security. Although all stored data can become unavailable -- if themedia it’s stored on is physically damaged, destroyed, or lost -- data stored on hard disks is at higher risk due to the mechanical nature ofthe device. Hard disk crashes are a common cause of data loss on personal computers. Regular system backups are the only effectiveremedy.1. Power failure and surgesPower problems (surges, blackouts, and brown-outs) can cause physical damage to a computer, inducing a hard disk crash or otherwiseharming the electronic components of the computer. Common mitigation methods include using surge suppressors and uninterruptiblepower supplies (UPS).2. Physical TheftPhysical theft of a computer, of course, results in the loss of confidentiality and availability, and (assuming the computer is ever recovered)makes the integrity of the data stored on the disk suspect. Regular system backups (with the backups stored somewhere away from thecomputer) allow for recovery of the data, but backups alone cannot address confidentiality. Cryptographic tools are available that canencrypt data stored on a computer’s hard disk. The CERT/CC encourages the use of these tools if the computer contains sensitive data or isat high risk of theft (e.g. laptops or other portable computers).IV. Actions home users can take to protect their computer systemsThe CERT/CC recommends the following practices to home users:Consult your system support personnel if you work from homeUse virus protection software
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Use a firewallDon’t open unknown email attachmentsDon’t run programs of unknown originDisable hidden filename extensionsKeep all applications (including your operating system) patchedTurn off your computer or disconnect from the network when not in useDisable Java, JavaScript, and ActiveX if possibleDisable scripting features in email programsMake regular backups of critical dataMake a boot disk in case your computer is damaged or compromisedFurther discussion on each of these points is given below.Recommendations13. Consult your system support personnel if you work from homeIf you use your broadband access to connect to your employer's network via a Virtual Private Network (VPN) or other means, youremployer may have policies or procedures relating to the security of your home network. Be sure to consult with your employer's supportpersonnel, as appropriate, before following any of the steps outlined in this document.14. Use virus protection softwareThe CERT/CC recommends the use of anti-virus software on all Internet-connected computers. Be sure to keep your anti-virus software up-to-date. Many anti-virus packages support automatic updates of virus definitions. We recommend the use of these automatic updates whenavailable.See http://www.cert.org/other_sources/viruses.html#VI for more information.15. Use a firewallWe strongly recommend the use of some type of firewall product, such as a network appliance or a personal firewall software package.Intruders are constantly scanning home user systems for known vulnerabilities. Network firewalls (whether software or hardware-based)can provide some degree of protection against these attacks. However, no firewall can detect or stop all attacks, so it’s not sufficient toinstall a firewall and then ignore all other security measures.16. Don't open unknown email attachmentsBefore opening any email attachments, be sure you know the source of the attachment. It is not enough that the mail originated from anaddress you recognize. The Melissa virus spread precisely because it originated from a familiar address. Malicious code might be distributedin amusing or enticing programs.If you must open an attachment before you can verify the source, we suggest the following procedure:be sure your virus definitions are up-to-date (see "Use virus protection software" above)save the file to your hard diskscan the file using your antivirus softwareopen the file
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For additional protection, you can disconnect your computer's network connection before opening the file.Following these steps will reduce, but not wholly eliminate, the chance that any malicious code contained in the attachment might spreadfrom your computer to others.17. Don't run programs of unknown originNever run a program unless you know it to be authored by a person or company that you trust. Also, don't send programs of unknownorigin to your friends or coworkers simply because they are amusing -- they might contain a Trojan horse program.18. Disable hidden filename extensionsWindows operating systems contain an option to "Hide file extensions for known file types". The option is enabled by default, but you candisable this option in order to have file extensions displayed by Windows. After disabling this option, there are still some file extensions that,by default, will continue to remain hidden.There is a registry value which, if set, will cause Windows to hide certain file extensions regardless of user configuration choices elsewherein the operating system. The "NeverShowExt" registry value is used to hide the extensions for basic Windows file types. For example, the".LNK" extension associated with Windows shortcuts remains hidden even after a user has turned off the option to hide extensions.Specific instructions for disabling hidden file name extensions are given in http://www.cert.org/incident_notes/IN-2000-07.html19. Keep all applications, including your operating system, patchedVendors will usually release patches for their software when a vulnerability has been discovered. Most product documentation offers amethod to get updates and patches. You should be able to obtain updates from the vendor's web site. Read the manuals or browse thevendor's web site for more information.Some applications will automatically check for available updates, and many vendors offer automatic notification of updates via a mailing list.Look on your vendor's web site for information about automatic notification. If no mailing list or other automated notification mechanism isoffered you may need to check periodically for updates.20. Turn off your computer or disconnect from the network when not in useTurn off your computer or disconnect its Ethernet interface when you are not using it. An intruder cannot attack your computer if it ispowered off or otherwise completely disconnected from the network.21. Disable Java, JavaScript, and ActiveX if possibleBe aware of the risks involved in the use of "mobile code" such as ActiveX, Java, and JavaScript. A malicious web developer may attach ascript to something sent to a web site, such as a URL, an element in a form, or a database inquiry. Later, when the web site responds toyou, the malicious script is transferred to your browser.The most significant impact of this vulnerability can be avoided by disabling all scripting languages. Turning off these options will keep youfrom being vulnerable to malicious scripts. However, it will limit the interaction you can have with some web sites.Many legitimate sites use scripts running within the browser to add useful features. Disabling scripting may degrade the functionality ofthese sites.Detailed instructions for disabling browser scripting languages are available in http://www.cert.org/tech_tips/malicious_code_FAQ.htmlMore information on ActiveX security, including recommendations for users who administer their own computers, is available inhttp://www.cert.org/archive/pdf/activeX_report.pdf
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More information regarding the risks posed by malicious code in web links can be found in CA-2000-02 Malicious HTML Tags Embedded inClient Web Requests.22. Disable scripting features in email programsBecause many email programs use the same code as web browsers to display HTML, vulnerabilities that affect ActiveX, Java, andJavaScript are often applicable to email as well as web pages. Therefore, in addition to disabling scripting features in web browsers (see"Disable Java, JavaScript, and ActiveX if possible", above), we recommend that users also disable these features in their email programs.23. Make regular backups of critical dataKeep a copy of important files on removable media such as ZIP disks or recordable CD-ROM disks (CD-R or CD-RW disks). Use softwarebackup tools if available, and store the backup disks somewhere away from the computer.24. Make a boot disk in case your computer
Top 75 Security ToolsIn May of 2003, I conducted a survey of Nmap users from the nmap-hackers mailing list to determine their favorite security tools. Eachrespondent could list up to 8. This was a followup to the highly successful June 2000 Top 50 list. An astounding 1854 people responded in'03, and their recommendations were so impressive that I have expanded the list to 75 tools! Anyone in the security field would be welladvised to go over the list and investigate tools they are unfamiliar with. I discovered several powerful new tools this way. I also plan topoint newbies to this page whenever they write me saying "I do not know where to start".Respondents were allowed to list open source or commercial tools on any platform. Commercial tools are noted as such in the list below.Many of the descriptions were taken from the application home page or the Debian or Freshmeat package descriptions. I removedmarketing fluff like "revolutionary" and "next generation". No votes for the Nmap Security Scanner were counted because the survey wastaken on an Nmap mailing list. This audience also means that the list is slightly biased toward "attack" tools rather than defensive ones.These icons are used: Did not appear on the 2000 listGenerally costs money. These rarely includes source code. A free limited/demo/trial version may be available.Works on LinuxWorks on FreeBSD/NetBSD/OpenBSD and/or proprietary UNIX systems (Solaris, HP-UX, IRIX, etc.)Supports Microsoft WindowsTranslations:Spanish Translation by ThiOsk (os_k&at&softhome.net) and Kerozene (kerozene&at&hackemate.com.ar)PortugueseTranslation by André Zúquete (avz&at&det.ua.pt)Here is the list (starting with the most popular):Nessus: The premier Open Source vulnerability assessment tool Nessus is a remote security scanner for Linux, BSD, Solaris, and otherUnices. It is plug-in-based, has a GTK interface, and performs over 1200 remote security checks. It allows for reports to be generated inHTML, XML, LaTeX, and ASCII text, and suggests solutions for security problems.
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Ethereal: Sniffing the glue that holds the Internet togetherEthereal is a free network protocol analyzer for Unix and Windows. It allows youto examine data from a live network or from a capture file on disk. You can interactively browse the capture data, viewing summary anddetail information for each packet. Ethereal has several powerful features, including a rich display filter language and the ability to view thereconstructed stream of a TCP session. A text-based version called tethereal is included.
Snort: A free intrusion detection system (IDS) for the massesSnort is a lightweight network intrusion detection system, capable ofperforming real-time traffic analysis and packet logging on IP networks. It can perform protocol analysis, content searching/matching andcan be used to detect a variety of attacks and probes, such as buffer overflows, stealth port scans, CGI attacks, SMB probes, OSfingerprinting attempts, and much more. Snort uses a flexible rule based language to describe traffic that it should collect or pass, and amodular detection engine. Many people also suggested that the Analysis Console for Intrusion Databases (ACID) be used with Snort.
Netcat: The network swiss army knifeA simple Unix utility which reads and writes data across network connections, using TCP or UDPprotocol. It is designed to be a reliable "back-end" tool that can be used directly or easily driven by other programs and scripts. At thesame time, it is a feature-rich network debugging and exploration tool, since it can create almost any kind of connection you would needand has several interesting built-in capabilities.
TCPDump / WinDump: The classic sniffer for network monitoring and data acquisitionTcpdump is a well-known and well-loved text-basednetwork packet analyzer ("sniffer"). It can be used to print out the headers of packets on a network interface that matches a givenexpression. You can use this tool to track down network problems or to monitor network activities. There is a separate Windows port namedWinDump. TCPDump is also the source of the Libpcap/WinPcap packet capture library, which is used by Nmap among many other utilities.Note that many users prefer the newer Ethereal sniffer.
Hping2: A network probing utility like ping on steroidshping2 assembles and sends custom ICMP/UDP/TCP packets and displays any replies.It was inspired by the ping command, but offers far more control over the probes sent. It also has a handy traceroute mode and supportsIP fragmentation. This tool is particularly useful when trying to traceroute/ping/probe hosts behind a firewall that blocks attempts using thestandard utilities.
DSniff: A suite of powerful network auditing and penetration-testing toolsThis popular and well-engineered suite by Dug Song includes manytools. dsniff, filesnarf, mailsnarf, msgsnarf, urlsnarf, and webspy passively monitor a network for interesting data (passwords, e-mail, files,etc.). arpspoof, dnsspoof, and macof facilitate the interception of network traffic normally unavailable to an attacker (e.g, due to layer-2switching). sshmitm and webmitm implement active monkey-in-the-middle attacks against redirected SSH and HTTPS sessions by exploitingweak bindings in ad-hoc PKI. A separately maintained partial Windows port is available here.
GFI LANguard: A commercial network security scanner for WindowsLANguard scans networks and reports information such as service packlevel of each machine, missing security patches, open shares, open ports, services/applications active on the computer, key registry
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entries, weak passwords, users and groups, and more. Scan results are outputted to an HTML report, which can be customized/queried.Apparently a limited free version is available for non-commercial/trial use.
Ettercap: In case you still thought switched LANs provide much extra securityEttercap is a terminal-based network sniffer/interceptor/loggerfor ethernet LANs. It supports active and passive dissection of many protocols (even ciphered ones, like SSH and HTTPS). Data injection inan established connection and filtering on the fly is also possible, keeping the connection synchronized. Many sniffing modes wereimplemented to give you a powerful and complete sniffing suite. Plugins are supported. It has the ability to check whether you are in aswitched LAN or not, and to use OS fingerprints (active or passive) to let you know the geometry of the LAN.
Whisker/Libwhisker: Rain.Forest.Puppy's CGI vulnerability scanner and libraryWhisker is a scanner which allows you to test HTTP serversfor many known security holes, particularly the presence of dangerous CGIs. Libwhisker is a perl library (used by Whisker) which allows forthe creation of custom HTTP scanners. If you wish to audit more than just web servers, have a look at Nessus.
John the Ripper: An extraordinarily powerful, flexible, and fast multi-platform password hash crackerJohn the Ripper is a fast passwordcracker, currently available for many flavors of Unix (11 are officially supported, not counting different architectures), DOS, Win32, BeOS,and OpenVMS. Its primary purpose is to detect weak Unix passwords. It supports several crypt(3) password hash types which are mostcommonly found on various Unix flavors, as well as Kerberos AFS and Windows NT/2000/XP LM hashes. Several other hash types areadded with contributed patches.
OpenSSH / SSH: A secure way to access remote computersSsh (Secure Shell) is a program for logging into or executing commands on aremote machine. It provides secure encrypted communications between two untrusted hosts over an insecure network. X11 connectionsand arbitrary TCP/IP ports can also be forwarded over the secure channel. It is intended as a replacement for rlogin, rsh and rcp, and canbe used to provide rdist, and rsync with a secure communication channel. OpenSSH is affiliated with the OpenBSD project, though aportable version runs on most UNIX systems. Note that the SSH.Com link above costs money for some uses, while OpenSSH is always free.Windows users may want to try the free PuTTY SSH Client or the nice terminal-based port of OpenSSH that comes with Cygwin. There aredozens of other clients (free or prorietary) available for most platforms - here is a huge list.
Sam Spade: Freeware Windows network query toolSamSpade provides a consistent GUI and implementation for many handy networkquery tasks. It was designed with tracking down spammers in mind, but can be useful for many other network exploration, administration,and security tasks. It includes tools such as ping, nslookup, whois, dig, traceroute, finger, raw HTTP web browser, DNS zone transfer, SMTPrelay check, website search, and more. Non-Windows users can enjoy online versions of many of their tools.
ISS Internet Scanner: Application-level vulnerability assessmentInternet Scanner started off in '92 as a tiny Open Source scanner byChristopher Klaus. Now he has grown ISS into a billion-dollar company with a myriad of security products. ISS Internet Scanner is prettygood, but is not cheap. So companies on a tight budget may wish to look at Nessus instead. A March 2003 Information Security magazine
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review of 5 VA tools (including these) is available here. Note that VA tools only report vulnerabilities. Commercial tools for actuallyexploiting them include CORE Impact and Dave Aitel's Canvas. Free exploits for some vulnerabilities can be found at sites like Packet Stormand SecurityFocus
Tripwire: The grand-daddy of file integrity checkersA file and directory integrity checker. Tripwire is a tool that aids system administratorsand users in monitoring a designated set of files for any changes. Used with system files on a regular (e.g., daily) basis, Tripwire can notifysystem administrators of corrupted or tampered files, so damage control measures can be taken in a timely manner. An Open Source Linuxversion is freely available at Tripwire.Org. UNIX users may also want to consider AIDE, which has been designed to be a free Tripwirereplacement. Or you may wish to investigate Radmind.
Nikto: A more comprehensive web scannerNikto is a web server scanner which looks for over 2000 potentially dangerous files/CGIs andproblems on over 200 servers. It uses LibWhisker but is generally updated more frequently than Whisker itself.
Kismet: A powerful wireless snifferKismet is an 802.11b network sniffer and network dissector. It is capable of sniffing using most wirelesscards, automatic network IP block detection via UDP, ARP, and DHCP packets, Cisco equipment lists via Cisco Discovery Protocol, weakcryptographic packet logging, and Ethereal and tcpdump compatible packet dump files. It also includes the ability to plot detected networksand estimated network ranges on downloaded maps or user supplied image files. Windows support is currently preliminary, so those usersmay want to look at Netstumbler if they run into trouble. Linux (and Linux PDAs like Zaurus) users may wish to also look at the Wellenreiterwireless scanner.
SuperScan: Foundstone's Windows TCP port scannerA connect-based TCP port scanner, pinger and hostname resolver. No source code isprovided. It can handle ping scans and port scans using specified IP ranges. It can also connect to any discovered open port using user-specified "helper" applications (e.g. Telnet, Web browser, FTP).
L0phtCrack 4 (now called "LC4"): Windows password auditing and recovery applicationL0phtCrack attempts to crack Windows passwordsfrom hashes which it can obtain (given proper access) from stand-alone Windows NT/2000 workstations, networked servers, primarydomain controllers, or Active Directory. In some cases it can sniff the hashes off the wire. It also has numerous methods of generatingpassword guesses (dictionary, brute force, etc). L0phtcrack currently costs $350/machine and no source code is provided. Companies on atight budget may want to look at John the Ripper, Cain & Abel, and pwdump3.
Automatically detect security vulnerabilities on your networkGFI LANguard Network Security Scanner (N.S.S.) checks your network for all potential methods that a hacker might use to attack it. By
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analyzing the operating system and the applications running on your network, GFI LANguard N.S.S. identifies possible security holes. Inother words, it plays the devil's advocate and alerts you to weaknesses before a hacker can find them, enabling you to deal with theseissues before a hacker can exploit them.Provides in-depth information about all machines/devicesGFI LANguard N.S.S. scans your entire network, IP by IP, and provides information such as service pack level of the machine, missingsecurity patches, wireless access points, USB devices, open shares, open ports, services/applications active on the computer, key registryentries, weak passwords, users and groups, and more. Scan results can easily be analyzed using filters and reports, enabling you toproactively secure your network - for example, by shutting down unnecessary ports, closing shares, installing service packs and hotfixes,etc.Patch managementGFI LANguard N.S.S. is also a complete patch management solution. After it has scanned your network and determined missing patches andservice packs - both in the operating system and in the applications - you can use GFI LANguard N.S.S. to deploy those service packs andpatches network-wide. It can also deploy custom software network-wide. >>
Why use GFI LANguard N.S.S.?>Check for unused user accounts on workstations>Audit your network for security vulnerabilities (Windows and Linux)>Detect unnecessary shares, open ports & unused user accounts on workstations>Check for and deploy missing security patches & service packs in OS & Office>Wireless node/link detection and USB device scanning>#1 Windows security scanner (voted by NMAP users & 200,000+ sold)>Unbeatable pricing: $575 for 100 IPs, $999 for unlimited IPs.