Вот что я получаю
root@vz198888:~# apt-get install p7zip-rar
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package p7zip-rar 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 'p7zip-rar' has no installation candidate
root@vz198888:~# apt-cache show p7zip-rar
N: Can't select versions from package 'p7zip-rar' as it is purely virtual
N: No packages found
Ubuntu 16.04 Server 64