Clearing arp-cache

Patrick McHenry · ‎08-30-2011

Hi,

is there a way to clear one arp-cache entry in the 6509s. I have a mac that has two IPs associated with it. I could clear the arp-cache of the whole vlan? Would this disrupt any users on this vlan? Also, any explanation of why this would happen? The user was recently moved from vlan 2 to 29. Thanks

Internet 170.117.57.210 1 0011.2567.d84d ARPA Vlan2

Internet 10.10.28.119 58 0011.2567.d84d ARPA Vlan29

I would have to wait three more hours for it to clear.

lgijssel · ‎08-30-2011

You could try it like this:

The following example shows how to refresh dynamically learned ARP cache entries for the host at 192.0.2.140:

Router# clear arp-cache 192.0.2.140 
 
 Link:
 http://www.cisco.com/en/US/docs/ios/ipaddr/command/reference/iad_arp.html#wp1011868
 
 regards,
 Leo

Patrick McHenry · ‎08-30-2011

Layer3Switch#clear arp-cache 10.10.XX.XXX?

% Unrecognized command

Doesn't recognize

version: 12.2(18)SXE2

lgijssel · ‎08-30-2011

Yeah, there is still a lot of difference between the router images and those for switches.

That's why I said "you can try".

This was a command introduced in 12.0 so if possible, it would have been in there.

Nevermind. Only two hours to go before the problem resolves itself!

regards,

Leo

Patrick McHenry · ‎08-30-2011

Thanks Leo. It was actually a dns issue. My Sys admin schooled me on it.

yadavsandip · ‎08-31-2011

Hi,

What i know abt Dns is, it resoves ip to hostname vice versa;

so how it is affected in ur case.