Question : Changing IP address and routing information on a Cisco 1720 router.

I am currently changing the IP addressing scheme on my network. I have three 1720 routers that connect two off site locations. I need to change the IP address of each router and the routing information to match. My current addressing scheme is 192.9.x.x . I am changing it to 192.168.x.x. I have access to all three routers. Is there a simple way to do this. If not then can you direct me to the information I will need to do it the hard way. Thanks in advance.

Answer : Changing IP address and routing information on a Cisco 1720 router.

OK, do the following:

On the 2nd router, type
enable
config t
router rip
 network 192.168.212.0
 network 192.168.250.0
interface Serial0
 ip address 192.168.250.2 255.255.255.0

You'll now lose your telnet session

On the main router, type
enable
config t
router rip
 network 192.168.210.0
 network 192.168.250.0
 network 192.168.251.0
interface Serial0
 ip address 192.168.250.1 255.255.255.0

end
copy runn start

now you should be able to get back into the 2nd router using the new address.
interface FastEthernet0
 ip address 192.168.212.250 255.255.255.0
router rip
 no network 192.9.212.0
 no network 192.9.250.0

end
copy runn start

verify that you have end to end connectivity. Then repeat with router 3 and the appropriate addresses and interfaces.
Then in router 1,
interface FastEthernet0
 ip address 192.168.210.252 255.255.255.0
router rip
 network 192.9.210.0
 network 192.9.250.0
 network 192.9.251.0
end
copy runn start

verify that everything is working.

done!