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Forum Discussion

JN_42992's avatar
JN_42992
Icon for Nimbostratus rankNimbostratus
May 27, 2010

http response not always fired

Hi, I have the iRule below deployed on a chassis running 9.3.1 (latest HF). This iRule does not always work. In fact, after some debugging, I noticed that HTTP_RESPONSE is not always fired. Any idea ...
application delivery
dev
devops
iRules
hoolio's avatar
hoolio
Icon for Cirrostratus rankCirrostratus
May 27, 2010
Hi Jean,

 

 

Are you using RAM cache on the HTTP profile for the virtual server? The HTTP_RESPONSE event is triggered when the pool member sends a response, LTM has an HTTP profile on the virtual server and LTM parses the response's HTTP headers. If a response is sent via RAM cache, HTTP_RESPONSE won't be triggered. Instead, CACHE_RESPONSE will be triggered when a response is sent.

 

 

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

 

 

You can use the CACHE::header command to retrieve or modify the headers that will be sent in a cached response:

 

 

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

 

 

If you're not using RAM caching on the VS, then is it possible that the server isn't sending a response when you don't see HTTP_RESPONSE triggered? Or do you have any other iRules added to the virtual server?

 

 

Aaron