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C_Guillaume_187's avatar
C_Guillaume_187
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Dec 03, 2013

RST/ACK sent by F5 loadbalancer to the client

Hello we actually have a problem on a specific VS. Context: my VS is a fastL4 profile with very standard configuration. This VS is called each second. And one time per hour we have an error, a TCP/RS...
application delivery
availability
big-ip ltm
LTM
C_Guillaume_187's avatar
C_Guillaume_187
Icon for Nimbostratus rankNimbostratus
Dec 03, 2013

yes, I made some tcpdump capture on the F5 to analyse more precisely the observed behavior. It's clear that the RST come from the F5. I checked health monitor and logs, and the server is always available.

 

My architechture is the following: (A)IP client <-> (B)IP VS - (C)IP back F5 <-> (D)IP server

 

I have two scenari of failure: first one connnection is established (at TCP level) and client/server are chatting during 10 sec there is no more traffic on the TCP connection D sends a FIN,ACK to C B relays the FIN, ACK to A A reply with an ACK to B B sends a RST,ACK to A <= this is my problem

 

second one: connnection is established (at TCP level) and client/server are chatting during 1 sec there is no more traffic on the TCP connection A sends a HTTP POST request to B B sends a RST,ACK to A <= this is my problem

 

If you want I can send the tcpdump (1Mo each)

 

Regards,