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

Forum Discussion

HenryO_166334's avatar
HenryO_166334
Icon for Nimbostratus rankNimbostratus
11 years ago

Keepalive v TCP Idle timeout

Hi   In relation to F5 Load balancing, could someone explain to me the difference between the Keepalive and TCP Idle timeout?   Client > F5 > Server in Server pool   Does one relate to clien...
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Kevin_Davies_40's avatar
Kevin_Davies_40
Icon for Nacreous rankNacreous
11 years ago

Keeping connections alive is the default for HTTP v1.1 which is currently the worldwide standard. Is is a header provided by the web browser whenever HTTP version 1.1 requests are used. See HTTP Persistent Connections

 

Connection: Keepalive

 

The TCP Idle timeout is the longest the F5 will keep a TCP client connection open when talking with the either side depending on the TCP profile you apply. See Solution ID 7606 for more information on the BIGIP TCP behaviour and its settings.

 

Peter_Z's avatar
Peter_Z
Icon for Cirrus rankCirrus
11 years ago
Kevin, I don`t think tcp keepalive, configured in the tcp profile is the same as HTTP keepalive you are mentioning. TCP profile settings will affect any L7 protocol..