When you call the individual f5 load port vs 80, the return value is null problem

status quo:

　　vs load port 80 and add XFF, pool comprises two member, member of the monitor port 80 & 9000.

Symptom:

　　Application colleagues describe a complete copy of said another member and add the return value is null problem occurs when invoked vs, no problem after the newly added server appears to the pool after disabled; directly call any one server no problem.

Failure Analysis:

　　After bypassing the problem does not happen again f5, so the problem lies in the preliminary judgment on f5. Start capture on f5 and see.

Troubleshooting:

　　After the capture f5 found a large number of retransmitted packets at the SNAT address of the proxy server to access the source added new request.

　　

　　Technical support at this time to ask f5 say never met.

　　After the capture on the issue of server also found that the above retransmission phenomenon.

　　The problem is then applied colleagues server restart. And then we found out that the retransmission packet capture disappears.

　　Ask if your developer colleagues said, troubleshooting.