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New Member

"show arp" indicates 'Incomplete' Hardware Addr

Here are the logs:

Router#sh arp

Protocol Address Age (min) Hardware Addr Type Interface

Internet x.x.x.102 0 Incomplete ARPA

Internet x.x.x.101 0 Incomplete ARPA

Internet x.x.x.100 0 Incomplete ARPA

Internet x.x.120.99 0 Incomplete ARPA

Internet x.x.120.98 1 0040.10xx.xxxx ARPA FastEthernet0/0

Internet x.x.120.97 - 000e.83f6.28b6 ARPA FastEthernet0/0

A firewall is connected to the FastEthernet port 0/0. Router can't see MAC address of computers behind it. What can we do ?

Thanks in advance.

3 REPLIES
Hall of Fame Super Silver

Re: "show arp" indicates 'Incomplete' Hardware Addr

zaqtivi

It is hard to understand the topology when you obscure so much of the addresses. That makes it more difficult to understand your situation and to make good suggestions.

If the router is trying ARP for these addresses then it must believe that they reside in the local subnet. If these devices are on a segment that is on the other side of the firewall then perhaps they should be defined as a different subnet and the router given a route to that subnet with the next hop address being the firewall.

If that does not help then perhaps you can be more clear about the situation and the topology.

HTH

Rick

Re: "show arp" indicates 'Incomplete' Hardware Addr

Hello,

in addition to Rick's post, what do you have configured as the default gateway on your clients ? Can your clients ping their default gateway ?

Regards,

GNT

New Member

Re: "show arp" indicates 'Incomplete' Hardware Addr

My apologies. They are all connected on the same subnet behind a firewall.

Router#sh arp

Protocol Address Age (min) Hardware Addr Type Interface

Internet x.x.120.102 0 Incomplete ARPA

Internet x.x.120.101 0 Incomplete ARPA

Internet x.x.120.100 0 Incomplete ARPA

Internet x.x.120.99 0 Incomplete ARPA

Internet x.x.120.98 1 0040.10xx.xxxx ARPA FastEthernet0/0

Internet x.x.120.97 - 000e.83f6.28b6 ARPA FastEthernet0/0

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