I have two Cisco 2811 routers connecting my my main and remote sites with private T1 connection. Both routers configured in IRB Bridge mode with BVI1 interface on each router. IP address assigned only to BVI interface.
So, I went to my main 2811 router and assigned an IP address to a FastEthernet interface. My thought is also to use this router as default gateway for my main site. This router in term would connect to my Cisco PIX.
I am using Class C public IP address on my network. So, my IP addresses on the interfaces as follows:
BVI1 - XXX.XXX.XXX.221
FA 0/1 - XXX.XXX.XXX.1
Subnet Mask: 255.255.255.255.
Without even physically reconnecting devices, as soon as I added IP address to FA 0/1, everyone lost internet connection. When I removed that IP address, everything went back to normal. I deleted ARP cache on one of the workstations and it found internet.
What am I doing wrong?