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rluyster's avatar
rluyster
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May 05, 2008

struggling with "action on service down"

We are running an appliction that is load-balanced over 2 servers. The problem that I am having is that due to the nature of this application, if one of the servers fails, it is impossible for them to...
management
monitoring
Manuel_Gabaldon's avatar
Manuel_Gabaldon
Icon for Nimbostratus rankNimbostratus
May 06, 2008
Hi,

 

 

Yes, you can force a Redirection, or even make a response telling your users about the issue. But you should know about the LB_FAILED event, since it will never be triggered if the real server has been marked down by a monitor. LB_FAILED only triggers when nobody is avalilable to handle your request:

 

http://devcentral.f5.com/wiki/default.aspx/iRules/LB_FAILED.html

 

It's the same thing with "action on service down".

 

 

What you should try to do is this: keep your user's session information (for instance, in the persistence table, with a lookup on the persistence table) and check the availability of its pool member before forwarding the request. You can do it with the lb:status commands.

 

 

http://devcentral.f5.com/wiki/default.aspx/iRules/LB__status.html

 

 

Regards.