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william_gonzalez's avatar
william_gonzalez
Icon for Altostratus rankAltostratus
Oct 06, 2022

Issues with Concurrent Connections VCMP i7800

Hi everyone,

Someone knows how many connections support a VCMP Guest with 6 Cores in a i7800 ? This because i have an issue with VS with 140K TCP Connections and suddenly differents pool in this F5 Guest gows down to 0 connections, the resolution in this moment is setting up a connection limit in VS with a lower value (10K e.g). I am supposing could be a performance limit but this platform in Datasheet support a higher value.

Thanks in advance.

application delivery
  • Nikoolayy1's avatar
    Nikoolayy1
    Icon for MVP rankMVP
    Oct 07, 2022

    Better check /var/log/ltm /var/log/kern and the tmm logs for a connection reaper because of memory issues or logs for the VIP.Also look for port exhaustion events or if the VIP cmp demoded  in the logs etc. Maybe also see if ePVA axceleration is in use and if attaching one connect profile to the VIP helps.

     

    This can be also application/network bottleneck issue where the app can't handle the stuff so the server and app teams need to also do their jobs so tcpdumps could be needed to see if the TCP transmit window is getting increased of the latency etc as F5 TCP optimized profiles will help. The pools could use the same network and servers/apps so check this. An issue I have seen is with different Time_wait settings between the F5 and the servers.

    https://support.f5.com/csp/article/K35612380

     

    If you have BIG-IQ for central F5managment it will help as BIG-IQ can show you latency etc without tcpdumps:

     

    https://clouddocs.f5.com/training/community/big-iq-cloud-edition/html/class3/module1/module1.html

     

    You will not find an easy answer weithout deep investigation.