Dch v DHCP

L Quc Ha

lqhoa@fit.hcmus.edu.vn

MC TIU BI HC

Gii thch cc khi nim c bn v dch v DHCP

Nm c qu trnh mt my tnh xin cp a ch IP

bng giao thc DHCP

Cch cu hnh dch v DHCP trn Windows 2008

Server

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NI DUNG

t vn

Gii thiu DHCP

M hnh hot ng

Trin khai dch v

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T VN

4

-IP/subnetmask -IP/subnetmask

-Default gateway

-DNS server

-.

-IP/subnetmask

-Default gateway

-IP/subnetmask

-Default gateway

-DNS server

200 hosts HCM

100 hosts H Ni

V SAO DNG DHCP?

DHCP lm gim phc tp v chi ph qun tr v s dng qu

trnh cu hnh TCP/IP ng.

DHCP lm gim phc tp v chi ph qun tr v s dng qu

trnh cu hnh TCP/IP ng.

Manual TCP/IP Configuration Manual TCP/IP Configuration

a ch IP c gn bng tay trc tip trn tng my trm.

Kh nng gn sai a ch IP cao.

Vic cu hnh sai c th dn n nhiu vn trong truyn thng v mng.

Chi ph qun tr tng cao trong mng c cc my tnh thng xuyn thay i.

a ch IP c gn bng tay trc tip trn tng my trm.

Kh nng gn sai a ch IP cao.

Vic cu hnh sai c th dn n nhiu vn trong truyn thng v mng.

Chi ph qun tr tng cao trong mng c cc my tnh thng xuyn thay i.

Automatic TCP/IP Configuration Automatic TCP/IP Configuration

a ch IP c cp pht t ng xung my trm.

m bo tt c cc my trm c cu hnh ng.

Cu hnh ti my trm c cp nht ng khi c s thay i trong cu trc mng.

Loi cc b nguy c c bn trn mng.

a ch IP c cp pht t ng xung my trm.

m bo tt c cc my trm c cu hnh ng.

Cu hnh ti my trm c cp nht ng khi c s thay i trong cu trc mng.

Loi cc b nguy c c bn trn mng.

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NI DUNG

t vn

Gii thiu DHCP

M hnh hot ng

Trin khai dch v

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DHCP GII THIU

DHCP = Dynamic Host Configuration Protocol

RFC 1533, 1534, 1541, 1542, 2131

Tin thn: BOOTP

Hot ng: tng ng dng trong m hnh OSI

Chc nng: cp pht a ch IP ng

M hnh Client - Server:

Server

Port: 67

Cung cp thng tin cu hnh TCP/IP cho cc client

Client:

Port: 68

Yu cu server cp thng tin cu hnh TCP/IP

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DHCP GII THIU

DHCP lm

Qun l tp trung a ch IP

Cp IP khi client cn

Qun l a ch IP

Li ch:

Gim thiu vic ng a ch IP

Ti u vic s dng a ch IP

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NI DUNG

t vn

Gii thiu DHCP

M hnh hot ng

Trin khai dch v

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DHCP

Non-DHCP Client Non-DHCP Client DHCP Client DHCP Client

DHCP Client DHCP Client

DHCP Server DHCP Server DHCP Database DHCP Database

IP Address1

IP Address2

IP Address3 . . .

IP AddressN

IP Address1

IP Address2

IP Address3 . . .

IP AddressN

IP Address2

IP Address1

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DHCP GI TIN

Xin cp mi:

Discover: client tm DHCP Server

Offer: DHCP gi mt a ch IP

Request: Client yu cu cp 1 a ch IP

Ack: Server xc nhn ng v gii phng a ch IP

Xin cp li:

Request

Ack

Hu thng tin c cp:

Release

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QU TRNH CP PHT IP

DHCP client broadcasts a DHCPDISCOVER packet DHCP client broadcasts a DHCPDISCOVER packet 1 1

DHCP servers broadcast a DHCPOFFER packet DHCP servers broadcast a DHCPOFFER packet 2 2

DHCP client broadcasts a DHCPREQUEST packet DHCP client broadcasts a DHCPREQUEST packet 3 3

DHCP Server1 broadcasts a DHCPACK packet DHCP Server1 broadcasts a DHCPACK packet 4 4

DHCP

Client

DHCP

Client

DHCP

Server1

DHCP

Server1

DHCP

Server2

DHCP

Server2

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QU TRNH GIA HN

DHCP Client DHCP Client DHCP

Server1

DHCP

Server1

DHCP

Server2

DHCP

Server2

DHCP Client sends a DHCPREQUEST packet DHCP Client sends a DHCPREQUEST packet 1 1

DHCP Server1 sends a DHCPACK packet DHCP Server1 sends a DHCPACK packet 2 2

50% of lease duration has

expired

50% of lease duration has

expired

87.5% of lease duration has

expired

87.5% of lease duration has

expired

100% of lease duration has

expired

100% of lease duration has

expired

If the client fails to renew its lease, after 50% of the lease

duration has expired, then the DHCP lease renewal process will

begin again after 87.5% of the lease duration has expired

If the client fails to renew its lease, after 50% of the lease

duration has expired, then the DHCP lease renewal process will

begin again after 87.5% of the lease duration has expired

If the client fails to renew its lease, after 87.5% of the lease has expired, then the DHCP lease generation process starts over again with a DHCP client broadcasting a DHCPDISCOVER

If the client fails to renew its lease, after 87.5% of the lease has expired, then the DHCP lease generation process starts over again with a DHCP client broadcasting a DHCPDISCOVER

DHCP Client DHCP Client DHCP

Server1

DHCP

Server1

DHCP

Server2

DHCP

Server2

DHCP client sends a DHCPREQUEST packet DHCP client sends a DHCPREQUEST packet 1 1

DHCP Server1 sends a DHCPACK packet DHCP Server1 sends a DHCPACK packet 2 2

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DHCP FORMAT MESSAGE

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DHCP FORMAT MESSAGE

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Operation Code 1 Loi thng ip

Hardware type 1 Loi a ch vt l

Hardware Length 1 Kch thc 1 a ch vt l

Hop Count 1 Client set l 0, dng cho relay agent

Transaction ID 4 Transaction ID,

Number of seconds 2 c in bi client

Flags 1 Cho bit gi tin ny c phi l gi tin broadcast

khng

Client IP address 4 a ch ca Client, dng trong cc trng hp

renew,..

Your IP address 4 a ch ca i tc

Server IP address 4 a ch ca next server miv c dng

trong cc thng ip DHCPOFFER, DHCPACK

Gateway IP address 4 a ch ca relay agent

Client Hardware addr 16 a ch vt l ca client

DHCP CC THNG IP TRAO I

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NI DUNG

t vn

Gii thiu DHCP

M hnh hot ng

Trin khai dch v

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DEMO

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M HNH DEMO

192.168.1.1/24

192.168.1.1/24

DHCP Client (Windows) DHCP Client (Windows)

DHCP Server DHCP Server

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BI TON

Yu cu: Trin khai dch v DHCP cc my trong

ng mng 172.29.70.0/24 v 172.29.90.0/24 c

th xin IP ng

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GII PHP 1: DHCP TRN MI SEGMENT

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DHCP SERVER - CONFIG

Xc nh tham s:

Dy IP m server s cp cho cc client yu cu

Start IP End IP

Subnet mask

a ch IP khng c cp t ng (Exclusions Range)

Default gateway, DNS,

a ch dnh ring (Reservation)

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GII PHP 1: DHCP TRN MI SEGMENT

Range: 172.29.70.x 172.29.70.y

Subnetmask: /24

Default gateway: ..

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Range: 172.29.90.x 172.29.90.y

Subnetmask: /24

Default gateway: ..

GII PHP 1: VN NY SINH

C nhiu segment mng

Cn nhiu DHCP server

Tn km: bo tr + phn cng

Gii php: DHCP Relay Agent

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GII PHP 2: DHCP RELAY AGENT

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DHCP Relay Agent

GII PHP 2: DHCP RELAY AGENT CU HNH

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Range: 172.29.70.x 172.29.70.y

Subnetmask: /24

Default gateway: ..

Range: 172.29.90.x 172.29.90.y

Subnetmask: /24

Default gateway: ..

DHCP Relay Agent

DHCP Relay Agent

Lng nghe gi tin Discover

GII PHP 2: DHCP RELAY AGENT HOT NG

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DHCP Relay Agent

DHCP - CLIENT

Chuyn sang ch Obtain an IP address

automatically

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DHCP CLIENT - LNH CONSOLE

Kim tra thng tin cu hnh IP: Ipconfig /all

Xin cp mt IP mi: Ipconfig /renew

Tr a ch IP ang dng: Ipconfig /release

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HI & P

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