Mar 27, 2026 - For details about updated CVE-2025-53521 (BIG-IP APM vulnerability), refer to K000156741.

Forum Discussion

Erik_B's avatar
Erik_B
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Jan 23, 2024

Virtual server for ICAP traffic

I need to build a virtual server which will receive ICAP traffic on port 1344. I've built a standard virtual server listening on port 1344 with the ICAP servers in the pool also listening on 1344. Th...
application delivery
Lucas_Thompson's avatar
Lucas_Thompson
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Jan 25, 2024

What happens if:

1- Change the number of pool members to 1 so you're only ever forwarding to one server.

2- Change the server type to FastL4 so BIG-IP does not get involved with app-layer traffic.

Once you do this, it should be almost exactly the same as directly connecting the ICAP and App Server.

  • Erik_B's avatar
    Erik_B
    Icon for Nimbostratus rankNimbostratus
    Jan 26, 2024

    Thank you. Yes, I did try this but no joy. I've been unable to find any other examples of this working so I am going to pivot and configure a wide-IP since the file server is able to successfully communicate with the ICAP servers.

    • Lucas_Thompson's avatar
      Lucas_Thompson
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      Jan 26, 2024

      Interesting! Glad you're making progress. If you want to continue looking at it, I'd recommend to examine packet captures taken from the ICAP server of direct-connect and by-bigip-connect modes to see what the difference is. It may be something as simple as a NAT or duplicate IP, or a routing problem.