ASM log shows http response : response was not logged because connection was reset

If it's repeatable and you can narrow it down to particular IPs I'd probably start with a tcpdump, client-side and server-side, have a look at flow.

I checked tcp dump , sever send ack repeated messages , when problem is occured ,and iwant to check if f5 ltm is root cause.

This setup is using snat (automap)

if you check the tcpdump and there are no resets during when the above occurs then you probably have to look better.

I will check it tomorrow again, shall rst messages appears from tcp dump?

Based on http response it looks that server (directly connected to same server subnet) reset connection

f5 ltm may cause the problem ?!?

assuming the message indicates a TCP RST packet has been involved then that should be clearly visible in the tcpdump.

my first guess would be it is the server (so pool member) that closes the connection, but it might be the BIG-IP for some reason. perform the TCP dump while getting this message and see where the TCP RST comes from. then investigate further.

please check the (21 is server) send rs to floating IP address , i am using SNAT MODE

please check the (21 is server) send rs to floating IP address , i am using SNAT MODE

please check the (21 is server) send rs to floating IP address , i am using SNAT MODE