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JN_AU's avatar
JN_AU
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Jun 16, 2023

Two virtual servers go down after an upgrade

Hi Everyone, I'm wondering if anyone has seen this behaviour before. After I perform an upgrade, two virtual servers out of about 10 go down. The applications using these VSs stop working, from the ...
  • JN_AU's avatar
    Oct 27, 2023

    Hi All,

    This looks to have possibly been this bug: https://my.f5.com/manage/s/article/K85805058

    The actual issue was on pool members behind the F5 - they used the F5s as a gateway to get to the internet using an IP forwarding VS. When the issue occurred these pool members were unable to get to the internet. It looks like the standard HTTPS health checks failed because the pool members were timing out trying to load internet content.

    After further examination of packet captures it was observed there was possibly async traffic (based on MACs observed).

    The fix was to create a new FastL4 profile and make sure 'loose init' and 'loose close' were enabled. This profile was then used on the ip forwarding VS, and it looks like this has solved the issue.

    14.1.5.6 was installed and is so far working fine.