Foundry Networks Switch and Router Installation And Configuration Manual page 523

Server
Server
FastIron Workgroup
Link Link
Activity Activity
Console
Power
Interface 2
Host 1
192.95.5.x
Sub-net 1
Figure 15.11 DHCP requests in a network with DHCP Assist operating on a FastIron
When the stamped DHCP discovery packet is then received at the router, it is forwarded to the DHCP server. The
DHCP server then extracts the gateway address from each request and assigns an available IP address within the
corresponding IP sub-net (Figure 15.12). The IP address is then forwarded back to the workstation that originated
the request.
NOTE: The DHCP relay function of the connecting router needs to be turned on.
December 2000
DHCP
Server
207.95.7.6
Step 3:
Router forwards the DHCP request to the
server without touching the gateway
address inserted in the packet by the switch
Router
Step 2:
FastIron stamps each DHCP request
with the gateway address of the
corresponding subnet of the
receiving port.
Interface 14
Host 2
Interface 8
200.95.6.x
Sub-net 2
Host 3 Host 4
202.95.1.x 202.95.5.x
Sub-net 3 Sub-net 4
Step 1:
DHCP IP address requests
for Hosts 1,2,3 and 4 in
Sub-nets 1, 2, 3 and 4
Configuring IP
Gateway addresses:
192.95.5.1
200.95.6.1
202.95.1.1
202.95.5.1
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