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New Member

Multicast Address

Hi

The following change request came in from one of our managend router customers.

arp 172.31.2.5 0100.aaaa.aab1 arpa

I believe they were installing a new firewall that requires a multicast address.

Can anyone explain what the above entry is actualy doing

Thanks in advance

3 REPLIES
New Member

Re: Multicast Address

That command just creates a static arp entry for 172.31.2.5 to point to 0100.aaaa.aab1

Not sure why a firewall would require that

New Member

Re: Multicast Address

Yes, I understand the static arp entry, my question is why would a firewall require this type of MAC Address.

Re: Multicast Address

Kevin,

There is nothing wrong about it, but it is odd.

There is no real logical reason to do this and i would query it.. other than to let them know that any device on that segment will process packet.

Also this could be a way they use load balancing , where both firewalls share a MAC (Kinda like HSRP) or used for redundancy.

This MAC is defs a locally admin address, as said i would defs query them on why they want to do this..

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