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New Member

can only ping with a source address

I am able to ping from switchA to switchB only when I specify a source address, however when I simply send icmp traffic across it fails.

any idea?

note that i can ping from all vlans to all vlans (when i specify the source), so all segments are allowed to pass, there is no access-group defined.

when i send a ping which source address does the switch use? is it the one with the lowest mac address?

can it be changed?

New Member

Re: can only ping with a source address

Your ping by default will use the ip address of the egress interface.


R1:f0/0  --> R2:f0/0

if you did a vanilla ipv4 ping from R1 to any R2 interface, it would use the source ip address of R1:f0/0

In your specific scenario, it would depend on the switch layer2/layer3 vlan and trunk design.

Can you pass over the configs of the two switches and the ping commands you are trying that fail?

Regards, Ash.