I have a raspberry pi at home which is behind a DD-WRT (build 18702) router. The Pi is running a ssh server on 192.168.1.137 port 22, and the router is directly connected to the internet. When I set up NAT from any chosen port on the WAN interface to the raspberry pi's IP address, the port will show up as "filtered" in nmap scans of my router's WAN IP. However, when I try to ssh in, like "ssh root@wanip -p 5000" the connection times out even though the port has clearly been opened, sshd is running on the Raspberry Pi.
So it looks like NAT is working properly on DD-WRT, but somehow it's still not reaching sshd on my raspberry pi. Where do I go from here?