High Packet Drop and connection failure

LTM-1 <> LTM-2 Fibre link directly attached without going over any SAN switch.

 

Ping from LTM-1 to LTM-2 actually goes thru the path LTM-1 (LACP) -> 2960-1 (PAGP) -> 2960-2 (LACP) -> LTM-2

 

Ping from LTM-1 to any node sitting under 2960-1 is actually using the same F5 subnet (subnet where the internal interface belongs).

 

Ping from LTM-2 to any node sitting under 2960-1 is actually using the same F5 subnet (subnet where the internal interface belongs).

 

 

Have performed tcpdump on F5 internal interface, F5 external interface, the Node as well as the client and found that there are actually quite a lot of TCP RST sent from the client. It is really strange, coz to perform this test, I have written one simple telnet script something like:-

 

 

telnet smtpserver 25 << EOF

 

QUIT

 

EOF

 

 

Any reason why the tcpdump show us the TCP connection being reset by client with this simple script? Seems like the TCP RST is being sent from the network layer instead but I really don't know why.

 

 

For we have tried to fail over from LTM-1 to LTM-2 but have not performed the tcpcapture nor doing any ping test. Would that give more information?