How to capture corresponding server side connection for a specific client ip when using SNAT. (Ver. 10.2.4)

The -p flag was introduced in 11.2 (I believe) to enable capturing peer flows. Prior to that it's a bit tricky. Please review the following for more information on pre-11.2 options:

sol11555: Gathering data in preparation for a traffic impacting change to the BIG-IP system

Here's an interesting thread that describes the peer flow option in 11.2:

https://devcentral.f5.com/questions/tcpdump-with-snat