F5 Drops WebSockets

Problem: F5 LTM is used als load balancer for multiple web servers. When the client opens a websocket connection to the web server, the connection is closed. Discussion: F5 LTM version before 11.6.0 has a bug in the request_log module (profile). The “request_log” module crashes and drops the connection. The bug is a known issue: https://support.f5.com/kb/en-us/solutions/public/16000/600/sol16690.html Solution: If you …

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F5 data flood

Problem: A F5 load balancer LTM sends lots of data to some clients. Sometimes this fills up all the available bandwidth with 1 Gbit or more. At the same time the input traffic does not raise. The traffic charts look like if F5 is attacking some clients (reversed DDoS :-) ) Discussion: After some time of staring …

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