I even have here a similar one:
systemctl status ssh
ssh.service - OpenBSD Secure Shell server
Loaded: loaded (/lib/systemd/system/ssh.service; enabled)
Active: failed (Result: start-limit) since Mi 2014-07-30 22:34:01 CEST; 2min 20s ago
Process: 20045 ExecStart=/usr/sbin/sshd -D $SSHD_OPTS (code=exited, status=255)
Main PID: 20045 (code=exited, status=255)
Jul 30 22:34:01 tuap systemd[1]: ssh.service: main process exited, code=exited, status=255/n/a
Jul 30 22:34:01 tuap systemd[1]: Unit ssh.service entered failed state.
Jul 30 22:34:01 tuap systemd[1]: ssh.service holdoff time over, scheduling restart.
Jul 30 22:34:01 tuap systemd[1]: Stopping OpenBSD Secure Shell server...
Jul 30 22:34:01 tuap systemd[1]: Starting OpenBSD Secure Shell server...
Jul 30 22:34:01 tuap systemd[1]: ssh.service start request repeated too quickly, refusing to start.
Jul 30 22:34:01 tuap systemd[1]: Failed to start OpenBSD Secure Shell server.
Jul 30 22:34:01 tuap systemd[1]: Unit ssh.service entered failed state.
root@tuap:/home/mylo# systemctl start ssh
root@tuap:/home/mylo# systemctl status ssh
ssh.service - OpenBSD Secure Shell server
Loaded: loaded (/lib/systemd/system/ssh.service; enabled)
Active: failed (Result: start-limit) since Mi 2014-07-30 22:36:53 CEST; 2s ago
Process: 2849 ExecStart=/usr/sbin/sshd -D $SSHD_OPTS (code=exited, status=255)
Main PID: 2849 (code=exited, status=255)
Jul 30 22:36:53 tuap systemd[1]: ssh.service: main process exited, code=exited, status=255/n/a
Jul 30 22:36:53 tuap systemd[1]: Unit ssh.service entered failed state.
Jul 30 22:36:53 tuap systemd[1]: ssh.service holdoff time over, scheduling restart.
Jul 30 22:36:53 tuap systemd[1]: Stopping OpenBSD Secure Shell server...
Jul 30 22:36:53 tuap systemd[1]: Starting OpenBSD Secure Shell server...
Jul 30 22:36:53 tuap systemd[1]: ssh.service start request repeated too quickly, refusing to start.
Jul 30 22:36:53 tuap systemd[1]: Failed to start OpenBSD Secure Shell server.
Jul 30 22:36:53 tuap systemd[1]: Unit ssh.service entered failed state.