I've been using github.com for a long time, but just had my ISP switch my home internet to a static IP and now I can't SSH to github.
What happens with SSH?
The id_ed25519 key has just been re-generated. SSH just stops:
$ ssh -T -F ~/.ssh/config git@github.com -vvv
OpenSSH_8.1p1, LibreSSL 2.7.3
debug1: Reading configuration data /Users/xxxx/.ssh/config
debug1: /Users/xxx/.ssh/config line 1: Applying options for *
debug1: Connecting to github.com port 22.
Wireshark shows it's not getting any return packets at all:
an screen capture of my wireshark showing TCP Retransmissions
So maybe SSH isn't allowed?
Maybe! But I can ssh to AWS EC2 instances fine from the same command prompt. No issues at all.
What else have I tried?
I can use SSH over HTTPS. For example, this...
ssh -T -p 443 git@ssh.github.com
...works fine and I can connect. But I need to know WHY plain ol' port 22 isn't working for me anymore.
What changed?
I asked my ISP to assign me a static IP. They've done this. It worked. Connections out from devices on my network appear to be coming from this new static IP they've assigned.
Content of ssh config
Host *
AddKeysToAgent yes
UseKeychain yes
IdentityFile ~/.ssh/id_ed25519
And as added bonus,
$ git config --list
credential.helper=osxkeychain
user.name=xxxx
user.email=xxx.xxx@xxx.com
core.autocrlf=input