Tunneling on a Vps hosted in the cloud

thomas.bucaioni

Hello,

When I try to open a forward tunnel on my Vps in the cloud, it works: ssh -p 22 -i mykey user@vps-public-ip -L 10000:vps-private-ip:80.
Then my local webrowser shows the page on the Vps when typing the address http://localhost:10000

But the reverse version doesn't: ssh -p 22 -i mykey user@vps-public-ip -R 10000:localhost:22
The goal would be to connect to my Pc at home from my workplace for example, or the opposite.

Any idea what goes wrong?
The port 10000 is open in the Networking webpage of the Vps, and in file /etc/ssh/sshd_config both ports 22 and 10000 appear.

marcinsdance

I've got a similar issue with Google Cloud Compute (Vps) - I can't figure out why reverse ssh tunnel doesn't work and how to make it work. It's very annoying as it's one of the most useful things. Anyone can help?

thomas.bucaioni

Hi @marcinsdance
Thanks for your support. Finally, I managed to get it work but I'm not sure what was the issue anymore...
If I remember well, the caveats were:

• open port 10000 on the cloud firewall
• do NOT listen on port 10000 with sshd
• add GatewayPorts yes in file /etc/ssh/sshd_config
• restart sshd on the Vps
• start sshd locally
• type ssh -v -p some-ssh-open-port -i ~/.ssh/vps-key user-on-the-vps@vps-PUBLIC-ip -R 10000:localhost:22 (here, 22 is on the local computer and 10000 is on the vps) on computer1 with user1
• type ssh -v -p 10000 -i ~/.ssh/vps-key user1-on-computer1@vps-PUBLIC-ip from computer2 with user2

and this should be pretty much it. Let me know if it doesn't work as it's 5mn fresh or so. Here are a bunch of links that helped me:

• https://www.youtube.com/watch?v=AtuAdk4MwWw
• https://www.youtube.com/watch?v=90d_whwkrNE
• https://superuser.com/questions/1194105/ssh-troubleshooting-remote-port-forwarding-failed-for-listen-port-errors
• https://kinsta.com/knowledgebase/ssh-connection-refused/