High Packet Drop and connection failure

since smtp connection is affected, i think it may be easier to investigate it (e.g. tcpdump on bigip and see if packet arrives at bigip or whether packet is dropped by bigip).

 

 

tcpdump -nni 0.0:nnn -s0 -w /var/tmp/output.pcap host x.x.x.x or host y.y.y.y or host z.z.z.z and port 25

 

x.x.x.x is virtual server ip

 

y.y.y.y/z.z.z.z is pool member ip

 

 

just my 2 cents.