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Sublimeboss31_3's avatar
Sublimeboss31_3
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Apr 22, 2019

javascript fails with var is undefined

We use F5 with several upstream servers without SSL termination, and after our application update we faced some strange issues with undefined variables and pending xhr requests. Is there some advices for configuring F5 for slow and big server responses, does tcp-lan-optimized profile suitable for it?

 

  • Hi Sublimeboss31,

    does tcp-lan-optimized profile suitable for it?

    Out of all build-in legacy profiles, the

    tcp-mobile-optimized
    profile is the best choice for HTTP traffic. This is even true if you don't use any mobile clients and also if you consider to use the profile on the client/server side.

    Stop Using the Base TCP Profile!

    https://devcentral.f5.com/articles/stop-using-the-base-tcp-profile

    F5 Unveils New Built-In TCP Profiles

    https://devcentral.f5.com/articles/f5-unveils-new-built-in-tcp-profiles-25175

    Cheers, Kai

  • Could this be an issue with different elements of the client-side code building in such a way that ajax requests are essentially remaining unfulfilled at the time the page is built.

     

    Do your apps have a lot/any ajax asynchronous content?

     

  • are you 100% sure it wasn't the update that caused the issue on the server side? have you tested it without the F5 BIG-IP in between?

     

    in general you tweak TCP profiles for better performance, but with any of the defaults it shouldn't have effects that cause time outs on the client side. unless perhaps very limited bandwidth or high latency links.