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

Forum Discussion

MattEWS_248690's avatar
MattEWS_248690
Icon for Nimbostratus rankNimbostratus
Feb 10, 2016

SSL Handshake Error

Hello, I'm fairly new to F5 but have unfortunately been tasked with updating all network connections to TLS 1.2 (only) To that end I'm simply trying to put a SSL enabled LTM Virtual Server in front ...
big-ip
LTM
security
Kevin_Stewart's avatar
Kevin_Stewart
Icon for Employee rankEmployee
Feb 11, 2016

Not sure which LTM version you're on, but server side TLS1.2 is supported in most platforms. There's a couple of things I'd try next:

  1. Open an SSH connection to the BIG-IP and issue an openssl s_client command to the server

    openssl s_client -connect x.x.x.x:9200

    What do you see? Does it succeed or fail? Does it indicate that Secure Renegotiation is enabled? If it fails, then you may have some unique TLS protocol or cipher requirements.

  2. Start an SSLDUMP capture on this internal interface

    ssldump -AdNn -i [internal VLAN name] port [encryption port]

    ssldump will show you the SSL handshake process and, hopefully, where the handshake is failing