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Kenny_Lussier_5's avatar
Kenny_Lussier_5
Icon for Nimbostratus rankNimbostratus
Jun 13, 2011

Tracking triggers in an iRule

Hi All,     I have the following iRule which checks a data group to see if the server is marked as online or off-line. If it is marked as online, traffic passes as normal, if it is off-line, it...
application delivery
dev
devops
iRules
hoolio's avatar
hoolio
Icon for Cirrostratus rankCirrostratus
Jun 13, 2011
Hi Kenny,

 

 

I don't think there is anything special you're doing in the iRule which would trigger a load balancing failure and the LB_FAILED event to run. You can check the LB_FAILED wiki page for details on when this event is triggered:

 

 

http://devcentral.f5.com/wiki/default.aspx/iRules/lb_failed

 

 

If this happens frequently, you could try capturing a tcpdump of the client and serverside traffic to see if the pool member is in fact not responding to LTM SYNs. For details on using tcpdump, check SOL411:

 

 

sol411: Overview of packet tracing with the tcpdump utility

 

http://support.f5.com/content/kb/en-us/solutions/public/0000/400/sol411.html

 

 

Aaron