1:7.2p2-4ubuntu2.4
) is not available, but a newer one is (1:7.2p2-4ubuntu2.8
). We redirected you there.
/usr/share/doc/openssh-server is in openssh-server 1:7.2p2-4ubuntu2.8.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/openssh-client