PF 2.2.5 log pre-nat IP

  • Relative to PFSense 2.2.5 release, I am logging via syslog to a SIEM. One thing I notice is that logs from the firewall come in post-NAT in that a firewall log message describing an allow/deny action has the public IP of the WAN interface of the firewall. Is there a way to log the pre-nat IP on this activity?

  • Rebel Alliance Developer Netgate

    Depending on the direction of the traffic and NAT that may not be visible.

    Blocks that happen on WAN with INBOUND traffic will have NAT applied before they reach the firewall rules. If the logs show that traffic with the WAN IP address as the destination, then there was no NAT involved.

    If you are blocking outbound it gets a bit trickier, outbound NAT applies before the rules as well so you can't see a local source there, just the WAN IP address.

    If you want to see local addresses you have to block inbound on a local interface

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