Very odd (to me) port forwarding issue.



  • I have a pretty standard home setup (internet -> modem -> pfsense -> lan switch -> lan), and am having some issues getting port forwarding to work.  I have already gone through the port forwarding troubleshooting on doc.pfsense.org, and have set it up exactly as described there.  After capturing packets on both the WAN and LAN, I can see both the TCP and UDP traffic that I'm forwarding coming in on the WAN.  I can also see it on the LAN side, but every single port forwarded packet (TCP or UDP) has an IP header checksum of 0x000.  Additionally, all of the TCP packets have had their destination port changed to a seemingly random port >10000, while the UDP packets retain their correct destination port.  The LAN machine that it's forwarding to ends up droppoing the packets because of their checksums.  What could be causing this type of issue?  All the other traffic comes through just fine with proper checksums.

    Thanks in advance for your help!



  • Can you show screenshots of your firewall and NAT rules?

    Did you enable advanced outbound nat?



  • @GruensFroeschli:

    Can you show screenshots of your firewall and NAT rules?

    Did you enable advanced outbound nat?

    I have not touched the outbound NAT settings; it's still set to the default of Automatic Advanced.

    Here are the pictures (I have tried it with and without the aliases)


Log in to reply