Configuring IP

Step 4:

DHCP Server extracts the gateway address from each packet and assigns IP addresses for each host within the appropriate range.

DHCP response with IP addresses for sub-nets 1, 2, 3, and 4:

192.95.5.10

200.95.6.15

202.95.1.35

202.95.5.25

DHCP

Server

207.95.7.6

v

Router

HP Switch 4000

Step 5:

Host 1 Host 1

Host 2

Host 2

IP addresses are distributed

192.95.5.10

 

 

to the appropriate hosts.

200.95.6.15

 

Sub-net 1

Sub-net 2

 

 

 

Hub

 

 

Host 3 Host 3

Host 4 Host 4

 

 

202.95.1.35

202.95.5.25

 

 

Sub-net 3

Sub-net 4

 

Figure 6.12 DHCP offers are forwarded back toward the requestors

Configuring DHCP Assist

You can associate a gateway list with a port. You must configure a gateway list when DHCP Assist is enabled on the HP 6208M-SX. The gateway list contains a gateway address for each sub-net that will be requesting addresses from a DHCP server. The list allows the stamping process to occur. Each gateway address defined on the switch corresponds to an IP address of the HP routing switch interface or other router involved.

Up to eight addresses can be defined for each gateway list in support of ports that are multi-homed. When multiple IP addresses are configured for a gateway list, the switch inserts the addresses into the discovery packet in a round robin fashion.

Up to 32 gateway lists can be defined for each switch.

USING THE CLI

EXAMPLE:

To create the configuration indicated in Figure 6.11 and Figure 6.12:

HP6208(config)# dhcp-gateway-list 1 192.95.5.1

HP6208(config)# dhcp-gateway-list 2 200.95.6.1

HP6208(config)# dhcp-gateway-list 3 202.95.1.1 202.95.5.1

HP6208(config)# int e 2

HP6208(config-if-2)# dhcp-gateway-list 1

HP6208(config-if-2)# dhcp-gateway-list 2

HP6208(config-if-2)# dhcp-gateway-list 3

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