BFD for connected

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Hi Team ,

I have a scenario as follows

Switch (port 48) ---------------------------- (port2/8) router
There are multiple MUX between switch and router.
These MUX are not in my control.

Config on switch is
configure vlan CPC_OM add ports 41-42, 48 tagged
configure vlan CPC_OM ipaddress
enable ipforwarding vlan CPC_OM

Lets say IP on router end is

1) When i bring port 48 on switch down ; the port on router stays UP (expected as MUX link is UP and fine)
2) As per my understanding ; BFD run on top of a 'client' protocol like static,bgp,ospf etc.
3) Here the link is a "connected" link . Hence I am not sure if BFD can be of any help here . Can someone please comment ?

My requirement is that when port on switch is brought down ; router should bring down interface and hence should delete 10.1.1.x route from its routing table.

I know BFD has to be done on both sides ; I wanted confirmation from extreme end if there is a possible solution to this case .

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Gaurav Madan

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Posted 2 years ago

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Erik Auerswald, Embassador

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BFD is used to check layer 3 (IP) connectivity. You can use it between layer 3 switches and routers, to bring down routing neighbors or next hops.

You seem to be looking for a layer 2 mechanism. CFM would be a standardized method for this, if the router supports it.