Yes, new major system upgrade new rules. If you’ve installed openssh server till Ubuntu 18 (Bionic Beaver) with just the simple command:
myuser@srv:~$ sudo apt-get install -y openssh-server Reading package lists... Done Building dependency tree Reading state information... Done Package openssh-server is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source E: Package 'openssh-server' has no installation candidate myuser@srv:~$
Now it is impossible as you can see. It is strange why they just did not include it as an alias just to prevent you from searching the Net (google?).
So there is a new way of installing OpenSSH server – it is a software collection called “OpenSSH server” and there is a new tool to manage such collections:
tasksel
So you must use tasksel to install OpenSSH server, here is the three command you should use:
sudo apt update sudo apt install tasksel sudo tasksel install openssh-server
And their explanation below in steps:
STEP 1) Update your server!
Because you could miss tasksel, it is not installed by default and even after clean install it seems not available before you do an update:
myuser@srv:~$ sudo apt update
STEP 2) Install tasksel
myuser@srv:~$ sudo apt install tasksel
STEP 3) Install OpenSSH server with tasksel
You are going to enter an console based graphic setup showing you the installation of the software collection “OpenSSH server”
myuser@srv:~$ sudo tasksel install openssh-server
Here is what is going to see after the above command:
* Throubleshooting – no tasksel packet!
Just DO NOT skip STEP 1) – update your package lists!!!
myuser@srv:~$ sudo apt install tasksel Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package tasksel