无法通过 SSH 连接到 GitHub（但可以连接到 GitLab）

Question

I've scoured the inte.net and found many people with similar problems, but my variant seems to be unique. The issue is I cannot connect to GitHub via ssh in order to push/pull (I'm on Windows 10).

If I run ssh -T git@github.com :

ssh: connect to host github.com port 22: Network is unreachable

If I run ssh -T -p 443 git@github.com :

Hi cjriches! You've successfully authenticated, but GitHub does not provide shell access.

Bizarrely, if I run ssh -T git@gitlab.com :

Welcome to GitLab, @cjriches!

This, combined with the fact that I tried disabling Windows Firewall to no avail, seems to prove that it's not just port 22 that's the problem. For what it's worth, I can also SSH into other, completely non-git-related hosts. For some reason, it's GitHub specifically that refuses to connect. I've re-uploaded the public key just in case, so the problem definitely isn't there.

Has anybody got any ideas how on earth this could be happening?

Answer 1

Seems like it is either a DNS issue or a Proxy issue. I would try changing my dns to 8.8.8.8 and 8.8.4.4. See if that clears up the issue. If that still doesn't rectify the issue, I would look and see if I am using a proxy which is preventing me from contacting github.

Answer 2

I had the same issue. Solve it by disabling the Virus Safe and Child Safe in the "Manage my Web Safe settings" section in the virgin broadband account page.

Source: https://community.virginmedia.com/t5/Forum-Archive/GitHub-inaccesible-over-SSH/td-p/3816287

Answer 3

Thanks to the OP and the other answers. My solution was to edit my ~/.ssh/config file (on linux).

Host github.com
HostName 140.82.121.4
User git
AddKeysToAgent yes
# Linux does not recognise UseKeychain but Mac does
IgnoreUnknown UseKeychain 
UseKeychain yes
IdentityFile ~/.ssh/your_ssh_key_file

Answer 4

Check git config --show-origin -l to see if there is any setting (proxy or others) that might apply to github.com specifically.

And check your environment variables (' set ' in a CMD in Windows), also to double-check if any of those variables might involves GitHub.

Answer 5

My solution was to enable SSH connections over HTTPS. See GitHub docs for more information.