I would mirror on the TX from the Trusted Network. I would mirror on the RX on the DMZ. (Presuming there is NO reason why the DMZ should be TX traffic to the Trusted side of the network). If DMZ is sourcing traffic to Internet, then maybe you can mirror on TX side then. I would mirror on the RX on the Internet (presuming you have switch on OUTSIDE of the current FW, so this is TX into the network, not being TX out to the Internet, as you already caught that traffic on the Trusted side TAP interface) I do not think you need to tap on VS for eval purposes. Use Vsys1.
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