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csm arp cache timeout issues

Hello all.

The arp cache timeout of the csm is normally 4 hours.

Now if we want to replace one of our servers we would need to wait 4 hours before the new servers mac address is learned if we keep the old ip-address.

I know we can manually flush one entry from the arp cache but is there a way for the csm to find out sooner if the mac address has changed?

I also know we can make the time shorter before the cache expires but what would be the consequences if we would put the timer to lets say 1000 seconds?

Would we then be flooding our network with arp requests all the time?

Finally I would expect that if an icmp request would fail because of the change of mac addres the csm would make an arp request to find out who has the ip I am trying to ping.

What is the procedure if the icmp request would fail?

Thank you.

Daniel Levi


Re: csm arp cache timeout issues

I would not suggest using the manual method, since it is time consuming and also there is a good chance that the new ARP request may load the CSM. I would suggest that you wait for the arp cache timeout.

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