NOC Services and Applications1 Sunday Folayan Nishal Goburdhan Isatou Jah.

NOC Services and Applications 1

NOC Services and Applications

Sunday FolayanNishal Goburdhan

Isatou Jah


What is Network Management?

“In order to operate a reliable service, the network must be managed according to a determined discipline, using a coherent structure of information management.”

Geoff Huston, ISP Survival Guide


What is a NOC?

Network Operations Centre (NOC) Monitors and manages a service provider’s

network• Information about current, historical and planned

availability of systems• Network status and operational statistics• Fault monitoring and management

Engineers can coordinate their work through the NOC


Network Management - Components

Parts of Network Management

• Configuration/Change management• Performance/Accounting management• Fault management • Security management


Configuration Management

Maintaining information relating to the design of the network and its current configuration

Network State• Record of network topology

– Static what is deployed where it is deployed how it is attached Who is responsible for it How do I contact them

– Dynamic operational status of the network elements



inventory management• database of network elements• history of changes & problems

directory maintenance• all hosts & applications• nameserver database

host and service naming coordination• "Information is not information if you can't find it"



Operational Control of network Start/stop individual components Alter configuration of devices Load and save config versions Hardware/Software upgrades Methods of access

• SNMPGet / SNMPSet• Out-of-Band access


RANCID

RANCID - Really Awesome New Cisco confIg Differ

Also works for IOS/CatOS/JunOS/...Open SourceRuns on FreeBSD, Linux, OSX, even MS-

Windowshttp://www.shrubbery.net/

(lots of other useful tools here too!)


RANCID

Collections of scripts that run from cron and automate • logging into routers• capturing configuration• highlighting configuration ‘differences’• emailing the ‘diffs’ to a mail list• installing ‘diffs’ into CVS


RANCID

• Track config changes– Normal day-to-day

• Track hardware changes– Where’s that spare…?

• Track (I)OS changes• Malicious changes ?

– What did your NOC do last night?

• Retrieve dead router configs.• Track router crashes!!


RANCID aka Big Brother

• Announce changes to entire team - everybody starts looking out for anyone making random changes!

• If it’s broken, what’s changed?• Make it user friendly - CVSWeb


RANCID Sample Output

!Slot 2/MBUS: hvers 1.1 !Slot 2/MBUS: software 01.36 (RAM) (ROM version is 01.33) !Slot 2/MBUS: 128 Mbytes DRAM, 16384 Kbytes SDRAM !- !Slot 6: 1 Port Gigabit Ethernet- !Slot 6/PCA: part 73-3302-03 rev C0 ver 3, serial CAB031216OL- !Slot 6/PCA: hvers 1.1- !Slot 6/MBUS: part 73-2146-07 rev B0 dev 0, serial CAB031112SB- !Slot 6/MBUS: hvers 1.2- !Slot 6/MBUS: software 01.36 (RAM) (ROM version is 01.33) !Slot 7: Route Processor !Slot 7/PCA: part 73-2170-03 rev B0 ver 3, serial CAB024901SI !Slot 7/PCA: hvers 1.4 !Slot 7/MBUS: part 73-2146-06 rev A0 dev 0, serial CAB02060044


RANCID Demo

Demo of live RANCID system


RANCID Re-use

More than configuration management.• Cheap Asset Tracker/NMS

UNIX script - easily extendible to other applications.• Re-use login scripts• Manage configuration changes

Correlate syslog and RANCID using Simple Event Correlator (SEC)

– http://threebit.net/mail-archive/cisco-nsp/msg00053.html


RANCID - Even More Uses

Looking Glass software

See Joe Abley and Stephen Stuart NANOG presentation:

• http://www.nanog.org/mtg-0210/abley.html

• Consistency/Audit checks• Generate DNS zone files• Create Topographic maps


What is SNMP?

Simple Network Management Protocol query - response system

• can obtain status from a device• standard queries• enterprise specific

uses database defined in MIB• management information base


What do we use SNMP for?

query routers for:• in and out bytes per second• CPU load• uptime• BGP peer session status

query hosts for:• network status• Message queues• Web traffic• Squid proxy load


SNMP Exercise



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SNMP driven display


Performance Management

A Consistent level of network performance Data collection

– interface stats– throughput– error rates– usage– percent availability

Data analysis for performance metrics and trends

Establishment of performance thresholds Capacity planning and deployment


Importance of Network Statistics

Accounting Troubleshooting Long-term trend analysis Capacity Planning Two different types

• active measurement• passive measurement

Management Tools have statistical functionality


MRTGSystem: bb-rtr.ws.afnog.org inMaintainer:Description: FastEthernet0/0.67-802.1Q-vLAN-subif Upstream LinkifType: Layer 2 Virtual LAN using 802.1Q (135)ifName: Fa0/0.67Max Speed: 12.5 MBytes/sIp: 196.216.67.254 ()


MRTG and MRTG Exercise


Netflow

Cisco developed - 1996 Initially a mechanism for forwarding

packetsNo longer - Now, primarily used for

• Accounting/Billing• Network planning• Peering arrangements• Traffic engineering• Security monitoring


Netflow

Netflow packet typically contains• IP SRC+DST• Port SRC+DST• Protocol information• TOS byte (DSCP)• Input logical interface (ifIndex)

Extendible (IOS capable) •AS / VRF / ...


Netflow

Uses CPU and memory!Export Netflow to external collector (or

use online on router)• http://www.splintered.net/sw/flow-tools/

Router summarisation possibleNetflow V5 is most commonly usedhttp://www.cisco.com/go/netflow


Netflow

Only works on inbound trafficUnidirectional flowShows transit (traffic through) and to the

router.Enabled by:

•ip route-cache flow•ip flow ingress (new syntax)

Output seen with: •show ip cache [verbose] flow


Netflow Example

From your workstation: ping 196.200.220.1

On your router:router# conf t

router(config) int fa0/0

router(config-if)# ip flow ingress

router# show ip cache flow


Netflow Example (cont).

What’s missing?(Why are the flows only in 1 direction?)

How do you fix it ?

Now repeat the BCP38 packet spoofing exercise, but track the bogus packets with Netflow. Pay attention to what happens when uRPF is enabled.


Netflow examples

Top ten lists (or top five) ##### Top 5 AS's based on number of bytes #######srcAS dstAS pkts bytes 6461 237 4473872 3808572766 237 237 22977795 3180337999 3549 237 6457673 2816009078 2548 237 5215912 2457515319

##### Top 5 Nets based on number of bytes ######Net Matrix----------number of net entries: 931777 SRCNET/MASK DSTNET/MASK PKTS BYTES 165.123.0.0/16 35.8.0.0/13 745858 1036296098 207.126.96.0/19 198.108.98.0/24 708205 907577874 206.183.224.0/19 198.108.16.0/22 740218 861538792 35.8.0.0/13 128.32.0.0/16 671980 467274801 ##### Top 10 Ports ####### input outputport packets bytes packets bytes119 10863322 2808194019 5712783 42730455680 36073210 862839291 17312202 138781709420 1079075 1100961902 614910 627542687648 1146864 419882753 1147081 41466321225 1532439 97294492 2158042 722584770


Accounting Management

What do you account for?• Use of the network and the services it provides

Types of accounting data• RADIUS/TACACS accounting data from Access

servers• Interface statistics• Protocol statistics

Accounting Data affects Business Models• Bill on usage?• Flat-rate billing?


Fault Management

Identify the fault• Regular polling of network elements

Isolate the fault• Diagnosis of the network components

Respond to the fault• Allocate resources to resolve the fault• Priority scheduling• Technical/management escalation

Resolve the fault• notification


Fault Management - systems

reporting mechanism• link to NOC• notify on-call personnel

setup & control alarm procedures repair/recovery procedures ticket system


Fault Management - Fault Detection

Who notices a problem with the network?• Network Operations Center w/ 24x7 operations staff

– open trouble ticket to track problem– preliminary troubleshooting– Assign engineer to problem or escalate ticket status

• Customer call• Other ISPs


Fault Management - Fault Detection (con)How can you tell if there is a problem with the

network?• Network Monitoring Tools

– common utilities ping Traceroute Ethereal Snmp

– Monitoring Systems NOCol Big Brother Nagios HP Openview, etc…

• Report state or unreachability– detect node down– routing problems


Fault Management - Ticket System

Very Important! Need mechanism to track:

• failures• current status of outage• carrier tickets


Fault Management:Ticket System

system provides for:• short term memory & communication• scheduling and work assignment• referrals and dispatching• oversight• statistical analysis• long term accountability


Fault Management - Ticket Usage

create a ticket on ALL calls create a ticket on ALL problems create a ticket for ALL scheduled events copy of ticket mailed to reporter and mailing

list(s) all milestones in resolution of problem maintain

the same ticket # ticket stays "open" until problem resolved Ticket reporter determines that ticket should be

closed.


Fault Management - Ticket Example

Sample opening ticketSubject Serial Number Fix sshd on E2 instructor machines 6

Area Queue none afnog-noc

Requestors Owner [email protected] inst

Status Last User Contact resolved Wed May 10 17:02:21 2006 (12 hr ago)

Current Priority Final Priority 1 1 Due No date assigned

Last Action Wed May 10 17:02:21 2003 (12 hr ago) Created Mon May 8 14:08:08 2003 (2 days ago)


Exercise: Ticket System•RT is already installed on http://e2-noc.ws.afnog.org

•Create tickets to track network occurrences as they occur - network failures will be provided ;-)


Fault Management - typical failures

• Node unpingable• no ip connectivity to router• possible reasons:

– serial link downcall telco

– router down/hardware problemcall engineer

– routing problem troubleshoot with tracerouterouteviews machine


Security Management: Do’s & Don’t’s

Dont’ leave things that are likely to be interesting to mice lying on the kitchen table overnight

Plug the holes that mice are using to get into the house Don’t provide places within the house for mice to build nests Set traps along walls where you often see mice out of the corner

of your eye Check the traps daily to rebait them and to dispose of squashed

mice. Full traps don’t catch mice, and they smell Avoid using commercial bait-and-kill poisons. Traditional snap

traps are best. Get a cat!


Security Management - Tools

security tools• cops - host configuration checker (www.cert.org)• swatch - email reports of activity on machine• Tcpwrappers – log connections, restrict access• ssh/skey – crypto authentication and communications• Tripwire – monitor changes to system files

Keep up to date with security information• bug reports

– CERT advisories mailing list: http://www.cert.org./contact_cert/certmaillist.html

• bug fixes• intruder alerts


Security Management – Good Practice

reporting procedure for security events• e.g. break-ins• abuse email address for customers to report

complaints ([email protected]) control internal and external gateways

• control firewalls (external and internal) security log management

• centralized logging host• Stealth logger, so it cannot be compromised


How do I manage my network?

Which tools should I use? What do I really need?• Keep it simple!• Need to consider engineers working remotely• Don’t want to spend too much time maintaining the

tool (it should be helping you!)• Different tools for NOC and engineers• Different tools for statistics• RELIABILITY!


References http://www.merit.edu/ipma/docs/isp.html http://www.nanog.org http://www.caida.org http://www.nlanr.net http://www.cisco.com http://www.amazing.com/internet/ http://www.isp-resource.com/ http://www.merit.edu/ipma http://www.ripe.net

http://www.ripe.net/


More Tools!

http://www.caida.org/Tools/• OC3Mon/Coral

http://www.merit.edu/~ipma– RouteTracker

– IRRj

– ASExplorer

http://www.geektools.com/ http://www.merit.edu/ipma/tools/other.html


SNMP Tool references

• MON - http://www.kernel.org/software/mon/• NOCol - ftp://ftp.navya.com/pub/vikas/nocol.tar.gz• Sysmon - ftp://puck.nether.net/pub/jared• Rover - http://www.merit.edu/~rover• Concord - http://www.concord.com• http://www.merit.net/~netscarf

http://www.kernel.org/software/mon/

ftp://ftp.navya.com/pub/vikas/nocol.tar.gz

ftp://puck.nether.net/pub/jared

http://www.merit.edu/~rover

http://www.concord.com/

http://www.merit.net/~netscarf

http://www.merit.net/~netscarf

NOC Services and Applications1 Sunday Folayan Nishal Goburdhan Isatou Jah.

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Transcript of NOC Services and Applications1 Sunday Folayan Nishal Goburdhan Isatou Jah.