My upgrade to Ubuntu LTS 22.04.1 from 20.04 was pretty smooth, but I ran into one issue. When I tried to ssh to a few other boxes around the network, I saw:
Unable to negotiate with 192.168.1.x port 22: no matching host key type found. Their offer: ssh-rsa,ssh-dss
Looks like I need to upgrade my ssh server on some machines. But I can’t do that if I can’t ssh to them! So I added a couple of lines to my /etc/ssh/ssh_config instead:
HostKeyAlgorithms ssh-rsa,rsa-sha2-512,rsa-sha2-256
PubkeyAcceptedKeyTypes ssh-rsa,rsa-sha2-512,rsa-sha2-256
I’ll need to undo that once I fix the server, but until then I can log into it.