Port Forward port 22 for Raspberry Pi 3 but port still closed

Question

Yesterday I made a Nas Server on Raspberry Pi and on the local network it's works fine and the SSH connection too but as soon as I try to connect to the Raspberry through Putty from an outside network it's not working.

I set a static IP for Raspberry and I port forwarded port 22 to the static IP but in the port checker it' s still closed.

I checked the ports on the Raspberry too and it says: "Listen" to port 22.

I have a ZTE f608 router.

I don't know what to do. If you guys have any ideas please share with me. Thank you.

Answer 1

You could try a port translation in your router’s settings. Say port 22222 from any public IP mapped to port 22 on the Pi’s local IP. Pick any valid port number above 1024. 22222 is just too obvious as an example. You will have to add the chosen port to the ssh command: ssh -p 22222 .... (I didn’t check that syntax. Look it up.)

Answer 2

Some ISPs apply port limitations on private internet connections. This is to prevent novice users from possibly harmful network settings.
You will have to ask your ISP about such limitations.
If that is the case you will not get around getting an commercial internet contract where no such limitation exists.

For instance in germany Vodafone does not even allow outbound connections to an SMB/CIFS share not even thinking about inbound limitations. It just blocks the assigned port completely.