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alexandre_girau's avatar
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Jan 11, 2018

Are there any 4k TCP Open connect limit per VS ?

Hi everyone,


1st, wish everyone in community an happy new year ;)


I'm actually facing an issue about a strange limitation with a BIG-IP LTM Virtual Edition in Cloud Azure. We don't have this limit if traffic go directly to nodes.


The traffic application that we try to pass trough F5, is a a TCP Socket and using 2 differents ports depending on client version. So we have 2 Standard VS, one for each client version. If we test charge 20k TCP socket on a single version, only 4k total is open on nodes ->


But if then we test charge 20k TCP socket again, but based on 2 differents version (so 2 VS), we have a total of 8k socket open on nodes, with 4k limit on each VS.


I'm wondering if I don't have a limit somewhere ? Based on licence ? I'm unable to see in log any limit reached and I've 0 in connection limit in VS.


Thank you for your help, Regards, Alex


PS : Using this version BIG-IP 13.1.0 Build 0.0.1868 Final


1 Reply

  • I'm not sure I can definitively answer this, but I would point out that there are configuration objects that can minimize the number of connections to the back end. For instance, oneconnect will reuse connections, reducing the number of back end connections.


    A review of your configuration and some specific traffic captures will likely show what is going on. Support can easily help you with this.