Interesting ARP Cache timeout

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We had an issue last night that might have been caused by a faulty ARP Cache entry. Turns out the time out for an ARP Cach is 14400 seconds which is 4 hours.

I noticed it when I did a show int [Interface]

ARP type: ARPA, ARP Timeout 04:00:00

So it looks like the ARP timeout is 14400 seconds (4 hours) by default.


The mac-address table has a default of 300 seconds by default.

PAS-Atlanta-6509-7#sh mac-address-table aging-time

Routed MAC aging time: 300 seconds (5 minutes)

Might want to keep this in mind when you make a add/move/change and clear arp and mac cams.