We have a point-to-point connection from a branch office to headquarters. The branch office accesses the Internet, voice and resources from headquarters. Both routers are Cisco 1721s. The branch office will get its own T1 access to the Internet. If we install a second T1 WIC card on the branch offices 1721 router, how can we direct Internet traffic through the second serial port? The branch office has "ip route 0.0.0.0 0.0.0.0 172.16.2.1 (headquarters serial point to point int.)
Yes, also you can use the backup solution offered by rburst above to backup the internet traffic in case of failure in the T1 link.
ip route 192.168.x.x 255.255.x.x s1
ip route 0.0.0.0 0.0.0.0 t1-interface
ip route 0.0.0.0 0.0.0.0 s1 253
The 2 static routes that you post should work and should do what you want. I would suggest that for backup purposes you might also configure a floating static default route so that if the branch loses their Internet T1 that they could route to HQ to get Internet connectivity as a backup. So it might look like:
ip route 0.0.0.0 0.0.0.0 s1 250
note that the 250 on the end is the administrative distance that makes this a floating static default route which would only be used if the primary static default route is removed from the routing table because of a problem with that T1.