Setting up router to pull multiple DHCP addresses

[Robert Milanovich]

Some cable providers provide multiple IP addresses with certain levels of internet service. Is it possible to have a router pull all the IP addresses available to it and put them in a pool so that machines behind it are not doing PAT?

For example, if I have 5 IP addresses (which must be pulled from DHCP...they are not static) available from the cable co, I can use one for the external of the router and then have the other 4 used for one to one NAT for machines behind the router.

[sbilgi]

You can do that by configuring a DHCP address pool.

http://www.cisco.com/en/US/products/sw/iosswrel/ps1831/products_configuration_guide_chapter09186a00800ca6b5.html#wp1000999

[Pavel Bykov]

What you are probably looking for is On-Demand Address Pool Manager (ODAP) and IPCP subnet mask feature combination. The combination uses first DHCP address for it's own interface and the rest for the NAT pool by assigning received IPCP subnet mask to the pool. Look into these areas.

ODAP:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122t/122t8/ftondhcp.htm#wp1015329

"On-demand address pools (ODAPs) support address assignment using the Dynamic Host Configuration Protocol (DHCP) for customers using private addresses"

IPCP:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121newft/121t/121t5/dtpppsub.htm#1015329

http://www.cisco.com/en/US/products/sw/iosswrel/ps1834/products_feature_guide09186a00800804b1.html

http://www.cisco.com/en/US/products/sw/iosswrel/ps1826/products_configuration_guide_chapter09186a00800d9b8c.html#xtocid1956410