ACE: Server- /backup-server connection failover

[maximilian.aschenbrenner]

Hi, I have a question regarding server-failover when using rserver+backup-rserver or serverfarm+backup-serverfarm (via sticky).

My understanding is, that in case a server fails, the existing connections will not fail over to a backup-server.

We are looking for a way to change that (default) behaviour - We've already searched the documentation etc. and found the "failaction reassign/purge". But when my colleague tried to have this confirmed via TAC, it got pretty confusing and we were told, there's no way to do/solve this..

So in a second attempt, does anyone have experience with this - maybe can confirm or give another solution?

Thanks & Regards,

Max

[ajayku2]

This was answered sometime back in few discussion:

first, not all servers accept TCP connection to be reassigned to them.

This is because tcp requires 3-way handshake and keeps track of sequence/ack numbers.Therefore, the servers need some way to exchange this information or to start in the middle.

On ace, we have 2 commands "failaction reassign" or "failaction purge".

The reassign is to simply move the connection to a backup server.

The purge is to kill the connection forcing the client to reopen a new one - this new connection will then be loadbalance to an active server.

[maximilian.aschenbrenner]

Thanks, actually I read that discussion, but needed an confirmation that I'm on the right track, after Cisco TAC told us the exact opposite..

Thanks!

[ajayku2]

Thats the best possible answer for this. Good to know it was helpful.

with regards,

Ajay Kumar