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Arp/Mac-address-table

When a cable is unplugged from a Cisco switch, how is the "down" port state advertised over the segment ? How are the cam and arp tables affected for the segment? Can the switch be forced to advertise a down port to inform nodes connected over trunk ports ?

I have 4 devices connecting LOCAL and REMOTE networks

2 3750 switches, A+B

2 2600 routers, C+D

LOCAL

A---B Trunk A-B

C---D Trunk C-D

REMOTE = 192.168.130.9/24

In A and B, Static routes to REMOTE network are redistributed through EIGRP to LOCAL.

Both static routes have admin distance of 10 to REMOTE ,for load balancing

In switch-A

ip route 192.168.130.9 255.255.255.248 C 10

ip route 192.168.130.9 255.255.255.248 D 10

In switch-B

ip route 192.168.130.9 255.255.255.248 C 10

ip route 192.168.130.9 255.255.255.248 D 10

Normally, these routes cause all traffic from A->REMOTE to be balanced

between A-C and A-B-D paths.

If the link B-D goes down, will the static route cause A to continue sending packets to B, even though D is down and B knows it ? Or will the switch somehow inform the rest of the segment ?

1 REPLY
Bronze

Re: Arp/Mac-address-table

Yes A would still send packets to B.In static routing router A should be manually configured to remove the route to the remote network.

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