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authenticationsshcommand-lineputtyngrok

Authentication is not working from PuTTY command line on ngrok

I have a Raspberry Pi set up as a download server at home. To access it from any Windows PC I download Putty and add its parent folder to the Path environment variable. When accessing it via SSH using Putty GUI or CLI from any PC on my home network, it attempts to login with an SSH key, if it fails it prompts me for a password, and I can login.

I set up an ngrok account to be able to access the server from work (ngrok uses the same address for all users, but each free user gets a specific port, randomized on server reboot). If i open up Putty's GUI and add the address (0.tcp.ngrok.io) and my port (13495) and click Open, I login normally, SSH key first, if that fails, password prompt, and I can login; as shown in the following picture: Putty GUI Login

However, if I login by command using "putty root@0.tcp.ngrok.io:13495" from the command line or making a Windows shortcut with that command as the target, it reacts as if password authentication is disabled and the only authentication method is via SSH key, which is not the case. (Failed Putty Logins)

I finally attempted to add the SSH key of my work desktop to the authorized_keys file, nothing changed. I can login by GUI using the key, but CLI login still fails.

I have tried resetting all of Putty's settings, redownloading, using Pageant instead of the Putty settings SSH>Auth, nothing works.

I have searched far and wide and delved into the creepy depths of the Internet and cannot find ANYONE with the same problem. If someone does find a post with the same question, well then that post must be running away from me. Help me, please. This is starting to get quite irritating.

Thanks in advance.

Solution

  • It's because PuTTY actually ignores everything after the colon (for a consistency with PuTTY psftp and pscp tools, where you specify a path after the colon).

    So the putty root@0.tcp.ngrok.io:13495 works like putty root@0.tcp.ngrok.io. That means you actually connect to the default SSH 22 port, not to the 13495.

    You have to use the -P switch to specify the non-default port:

    putty root@0.tcp.ngrok.io -P 13495