jeltsch's blog

1. Enable root login with password on the server. To do so, you need to edit the file /etc/ssh/sshd_config.
   Modify the lines starting with "PermitRootLogin" like this:
   #PermitRootLogin prohibit-password
PermitRootLogin yes
2. Restart the sshd server:
   sudo systemctl restart sshd
3. On the client, copy the public key files to the server with the ssh-copy-id command:
   ssh-copy-id root@server
4. On the server, disable root login with password and enable root login with public key authentication:
   

After switching computers (but staying on the same version of Ubuntu), I copied my openvpn configuration (/etc/openvpn) to the new system. And when I booted next time, I received a weird request during boot to type in my username and password. There was no mentioning for what purpose, so I had to guess. Additionally, there is a bug that required me to press twice the Enter key after the username and password. It appeared to be openvpn, which tried - by default - to start up all openvpn configurations that it could find in /etc/openvpn.

In an Ubuntu 18.04 two disk setup (/ on SSD, /home on spinning drive), my Ubuntu 18.04 has still defaulted to use swap space on the SSD although there was a swap partition of the same size on the spinning drive. This was not a new install, but a system upgrade from 16.04 (where I had created a swap partition manually on the spinning drive to spare the SSD). Linux is able to determine whether a drive is spinning or not, but apparently the installation/upgrade script was not very smart.