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Forum Discussion

TD-Bernie's avatar
TD-Bernie
Icon for Nimbostratus rankNimbostratus
Sep 19, 2023

Connection reset by peer via Standard Virtual Server

Hello, I got an api backend service behind an F5, the problem is if Virtual Server is Standard then client gets "Connection reset by peer", the problem is disapeared if i switch to Performance (HTTP...
application delivery
Mohamed_Ahmed_Kansoh's avatar
Mohamed_Ahmed_Kansoh
Icon for MVP rankMVP
Sep 19, 2023

Hi TD-Bernie, 

- Enable rest cause ( Log & Packet ) >>> https://my.f5.com/manage/s/article/K13223


- Check /var/log/ltm >> while applying http profile. 
- Take a Pcap again >> and check all of reset packets. 
Note ( Do that while applying http profile ) 
- Also Create custom http profile >>> try to modify Maximum header size & header count. 
Refer to those articles : 
https://my.f5.com/manage/s/article/K8482 
https://my.f5.com/manage/s/article/K22518624

>>> you can share the Pcap if you want to have a look. 

Thanks

 

  • TD-Bernie's avatar
    TD-Bernie
    Icon for Nimbostratus rankNimbostratus
    Sep 21, 2023

    Hello Mohamed,

    I am not sure the root cause of this problem, but it seems to be network issue cause i checked at that night, the connection was okay again, it kept unstable until i tried to change ip address of virtual server (i could make sure there is no ip conflict).

    Thank you.