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Forum Discussion

kimjim_51067's avatar
kimjim_51067
Icon for Nimbostratus rankNimbostratus
Mar 20, 2012

I need to create an irule that will reject a specified percnetage of traffic.

Can some one help me in creating an irule that will reject percentage (ex- 50%) of the traffic .   I need this because when there is a heavy traffic my systems are unable to handle ,so i want to a...
application delivery
dev
devops
iRules
hoolio's avatar
hoolio
Icon for Cirrostratus rankCirrostratus
Mar 27, 2012
I like your thinking TDK. But using a local variable for this would be specific to that TCP connection. So if you use that logic, every other HTTP request to the specific URI on each TCP connection would be dropped. I'd guess this wouldn't lead to dropping 50% of requests as some (or most?) clients would not reuse their TCP connections to make multiple requests to that specific URI.

 

 

You could use a session table entry to create a flag that you increment and then reset to 0 (https://devcentral.f5.com/wiki/iRules.CMP_v10_compatible_counters_using_the_session_table.ashx).

 

 

However, using expr will give a much more even distribution compared with a local variable, regardless of the connection reuse behavior of clients. And it doesn't require any session tracking complexity.

 

 

Aaron