ARP cache on Router not correct

Unanswered Question
Sep 2nd, 2007
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Router A has a LAN interface with 2 physical ip address(pri + secondary IP). The primary inf is connected to the same firewall segment. The secondary inf is connected to the switch management IP.

After various ping to the secondary IP( from the switch, which failed, i did a 'show arp' on the router and realised that the switch ip is binded dynamically to the firewall MAC instead of the switch(3com) MAC.

interface Ethernet0/0

ip address secondary

ip address

ipx network 1


Can anyone explain this? Is it a bug?

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chronix Sun, 09/02/2007 - 23:51
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RouterA#show arp | in a373

Protocol Address Age (min) Hardware Addr

Internet 120 0000.a710.a373

Internet 120 0000.a710.a373

Internet 120 0000.a710.a373

Internet 120 0000.a710.a373

0000.a710.a373 is the MAC of the checkpoint Inf.

IPs are the switch mngt IP.

nambi_gct Mon, 09/03/2007 - 03:05
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Is there any possibility of duplicate addresses.Please check the logs with "show logging" and look for any messgages.

ohassairi Mon, 09/03/2007 - 10:33
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try to eliminate the firewall and then ping the router, may be the firewall configuration is the cause


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