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Routing between Primary and Seconday IP addresses

I am using a Cisco 871 router. The internal interface is configured with a primary IP address of 192.168.1.1 and a secondary IP address of 10.0.0.1. I also have an Internet facing interface that gets it's IP address from the ISP's DHCP lease.

72.x.x.x.x represents the DHCP address on my external interface.

192.168.0.x represents the internal network or LAN.

10.0.0.0 represents a PAT forward to a firewall from the External interface.

I want to replicate behavior that a person would experience coming from the Internet so I want to route packets between the 2 IP's. Can this be done?

Reply to
Paul
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It's the automatic default behaviour so it should "just work"(tm) unless you've doen something to stop it.

Reply to
Martin Gallagher

primary IP address of 192.168.1.1 and a

that gets it's IP address from the ISP's DHCP

What interfaces contain the 192.168 and 10.* IP addresses ? Some BVI interface ?

I am not sure you want to "route" between the two. You may have to replicate your IP NAT commands to have the last argument the 10.* interface instead of the Dialer interface and add the apprpriate IP NAT inside/outside commands to the interface definitions to "link" the two subnets.

I haven't done this so not sure it will work.

To route beween two subnets in my case:

I have BVI 10 with 10.0.0.1/16 and Fast/Internet 4 with 10.1.0.1/16

I added "ip route 10.1.0.0 255.255.0.0 fa 4 permanent" to the config. It appears to work, but have not tested all possible convolutions.

Reply to
JF Mezei

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