topic Re: ASA GARP in Network Security

ASA GARP

stephen.stack — Mon, 11 Mar 2019 17:13:37 GMT

Hi All,

Just wondering is any knows how to have an ASA process a GARP (gratuitous ARP)?

It appears that ASAs ignore them, therefore i have Linux HA that does not work beacuse the

ASA retains the original arp and ages out after four hours.

Thanks for your help

Stephen

Re: ASA GARP

Panos Kampanakis — Tue, 23 Feb 2010 22:46:05 GMT

The ASA should honor the GARPs. In the arp debugs you will see something like

arp-in: updating gratuitous ARP 172.16.256.78 - xxxx.xxxx.xxxx

If the asa has an arp entry, and then sees a conflicting gratuitous arp reply with a different MAC for that same IP, we will replace the arp entry we have with the new entry. We will also log a syslog at level 4 stating that there was a collision. I would suggest you to check the asa syslogs and debugs to see if we see evidence of these collision syslogs.

I hope it helps.

Re: ASA GARP

Kureli Sankar — Wed, 24 Feb 2010 01:07:54 GMT

See if you have a static arp configured.

Check the ASA's talbe "sh arp | i aaa.bbb.ccc and see if the mac shows and if it appears correct.

Issue "sh run arp" to make sure you don't have any conflicting entries added statically.

-KS

Re: ASA GARP

stephen.stack — Thu, 25 Feb 2010 08:57:31 GMT

Thanks very much for the replies guys, I am taking that is not working on second hand info.

I need to see this happening for myself, but at least i know that the ASAs accept GARPS.

I will update once i know more.

Regards

Stephen