So the LAN side is going to your ASA? and Internet is going out through the Layer 3 switch? If that is the case I'm not sure you'll see client data since the ASA will show all data leaving it as itself. I think you'd need the MX behind the ASA unless I'm not understating your topology.
Adam R MS | CISSP, CISM, VCP, MCITP, CCNP, ITILv3, CMNO
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