I am trying to create a homemade server. I'm running Ubuntu 18.04 and have an Xfinity router. I've forwarded port 22 to a reserved local IP for my server.

The problem is that I can connect via a different network (using my iPhone hotstop), but only for about 3 minutes after my router starts up. At this time the xfinity gateway (https://internet.xfinity.com/network/advanced-settings) is unresponsive which I guess means it's still starting up. After about three minutes the page loads, and I'm no longer able to connect via ssh. Any help would be super appreciated - thanks all!

  • Try a different port on the "outside". I've found routers assigning 22 for their own internal use. Commented Sep 26, 2019 at 12:54
  • Don't expose your ports you are trying to connect from outside, its bad practice. Bots scan for open common ports and will hit you hard. Use a custom port and then forward it to 22 internally. Anytime a service misbehaves you should go and check logs. If information there is not sufficient, you should increase verbose level if possible. The answer to your question should be available in sshd logs, so make sure you check the logs: cat /var/log/auth.log | grep sshd Commented Sep 26, 2019 at 15:42

1 Answer 1


Update: the problem was the router’s firewall. Even on low security it blocked incoming traffic. Seems like kind of a gaping vulnerability for the firewall to take longer to start up than the router @xfinity (which is why I was able to ssh only for a few minutes after start up). Oh well, thanks everybody!

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