Forum Discussion
DennyK_144735
Nimbostratus
Well, we have found a workaround that resolves this issue; when we set the Source Port setting to "Change" instead of "Preserve", the translated ports it assigns are chosen sequentially instead of randomly, which resolves the issue with ports being re-used too quickly. Don't know why the assigned ports are random with "Preserve" but sequential with "Change", but it does fix the problem.
daboochmeister
May 21, 2014Cirrus
When you set source port to "preserve" or "preserve strict", the incoming port used by the client accessing will be used. That port is typically chosen at random by the network stack on the client; so the apparent randomness you're seeing on the F5 is a result of the F5 simply using that randomly-selected port. And if you have multiple clients incoming, it is possible to get conflicts (unless you e.g. set up a large SNAT pool).