Issues with ssh connection to our work host persist - although we can make it to the gates, we can't get home. Assuming this is a result of system downstairs mixup during 22.04 installation. So start again.
sudo apt-get remove openssh-server openssh-client
sudo apt-get install openssh-server openssh-client
# have a luuk
man sshd_config
# backup
sudo cp /etc/ssh/sshd_config /etc/ssh/sshd_config.original
sudo chmod a-w /etc/ssh/sshd_config.original
# edit the sshd_config, sudo nano etc
# set the banner to display at login, resisting slide into verbosity
Banner /etc/issue.net
# BEFORE RESTARTING, test the config to make sure its sane
sudo sshd -t -f /etc/ssh/sshd_config
# or whathaveyou, then save and restart
sudo systemctl restart sshd.service
# authorised keys are actually those of our home-grown champion, adjutant. Move those keys over, correct the permissions:
chmod 600 ~/.ssh/id_rsa_homegrown # only author can only read/w
chmod 644 ~/.ssh/id_rsa_homegrown.pub # anyone can read, author can write
# propegateway, note you specify the private key
ssh -i ~/.ssh/id_rsa_homegrown author@gateway
Hopefully that extremely specific solution is of use to you. If not - back to bed.