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CEnroth's avatar
CEnroth
Icon for Nimbostratus rankNimbostratus
Oct 31, 2023

LTM Policy don't trigger on ALPN in SSL_Client_Hello

Hi

Have someone successfully managed to get a LTM Policy to trigger on ALPN in "SSL Client Hello"?

I have created a policy like below, and attached it to a Virtual-Server.
But when I send/connect to VS, policy won't trigger and nothing is written to my log.
I have also tried with different Index values, but that makes no difference.

I have verified that the ALPN is present in TLS request, both with Wireshark but also with an iRule attached to same VS.

iRule:

WireShark:

Regards
Christian

 

 

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  • Niels_van_Sluis's avatar
    Niels_van_Sluis
    Icon for MVP rankMVP
    Nov 03, 2023

    I've been playing with this, but also couldn't get it to work. It's unclear what index the SSL Extension alpn in the policy would be a valid one.

    • CEnroth's avatar
      CEnroth
      Icon for Nimbostratus rankNimbostratus
      Nov 03, 2023

      Hi Niels

      I really appreciate your help. For a while i thought i had done something wrong. But if you have tested it, and
      also can't get it to work then I’m quite sure that it is a "bugg" in the way Big IP handles ALPN in TLS packages.

      I will open a case towards F5, and see what kind of solution they will come up with.

      Regards
      Christian