same ARP entry on two different interfaces

[from88]

Hello,

I have a CPE with two interfaces (for redundancy purposes).

Because of network topology the CPE have two SAME ARP entries (same ip - same mac) but on multiple different interfaces:

something like this:

IP1 - AAAAA Fa0/0

IP2 - AAAAA Fa0/1

The routing table points through Fa0/0. Seems like everything works fine, but my question is in general. Do this implementation, when router learn same arp from different interface, can bring any problems? Personally it's quite strange, but i dont see any problems with that why it should not work. Router have a default route point to FA0/0, and the traffic is forwarded accordingly.

Any other opinion ? Thanks

[Philip D'Ath]

As long as only one interface talks at a time it will be fine.  If both interfaces were to generate traffic, and this was plugged into a switch, the switch forwarding table would keep getting it updated throwing the traffic from one interface to the other.