MacBook-Pro-Pavel:demo pavel$ docker-machine ssh regru

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Last login: Wed Jul 12 11:07:24 2017 from 91.239.5.122
root@regru:~# systemctl status docker.service
● docker.service - Docker Application Container Engine
   Loaded: loaded (/lib/systemd/system/docker.service; enabled)
  Drop-In: /etc/systemd/system/docker.service.d
           └─10-machine.conf
   Active: failed (Result: start-limit) since Wed 2017-07-12 11:14:42 MSK; 11min ago
     Docs: https://docs.docker.com
  Process: 14329 ExecStart=/usr/bin/docker daemon -H tcp://0.0.0.0:2376 -H unix:///var/run/docker.sock --storage-driver aufs --tlsverify --tlscacert /etc/docker/ca.pem --tlscert /etc/docker/server.pem --tlskey /etc/docker/server-key.pem --label provider=generic (code=exited, status=1/FAILURE)
 Main PID: 14329 (code=exited, status=1/FAILURE)

Jul 12 11:14:42 regru systemd[1]: docker.service: main process exited, code=exited, status=1/FAILURE
Jul 12 11:14:42 regru systemd[1]: Failed to start Docker Application Container Engine.
Jul 12 11:14:42 regru systemd[1]: Unit docker.service entered failed state.
Jul 12 11:14:42 regru systemd[1]: docker.service start request repeated too quickly, refusing to start.
Jul 12 11:14:42 regru systemd[1]: Failed to start Docker Application Container Engine.
Jul 12 11:14:42 regru systemd[1]: Unit docker.service entered failed state.
root@regru:~# journalctl -xn
-- Logs begin at Wed 2017-07-12 10:52:35 MSK, end at Wed 2017-07-12 11:26:08 MSK. --
Jul 12 11:25:44 regru sshd[14368]: Accepted publickey for root from 91.239.5.122 port 61397 ssh2: RSA 8c:ad:45:e9:d5:a6:26:ad:d5:c3:5f:08:8e:b6:b2:18
Jul 12 11:25:44 regru sshd[14368]: pam_unix(sshd:session): session opened for user root by (uid=0)
Jul 12 11:25:58 regru sshd[14377]: error: Could not load host key: /etc/ssh/ssh_host_ecdsa_key
Jul 12 11:25:58 regru sshd[14377]: error: Could not load host key: /etc/ssh/ssh_host_ed25519_key
Jul 12 11:26:00 regru sshd[14377]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=116.31.116.10  user=root
Jul 12 11:26:02 regru sshd[14377]: Failed password for root from 116.31.116.10 port 21404 ssh2
Jul 12 11:26:05 regru sshd[14377]: Failed password for root from 116.31.116.10 port 21404 ssh2
Jul 12 11:26:07 regru sshd[14377]: Failed password for root from 116.31.116.10 port 21404 ssh2
Jul 12 11:26:08 regru sshd[14377]: Received disconnect from 116.31.116.10: 11:  [preauth]
Jul 12 11:26:08 regru sshd[14377]: PAM 2 more authentication failures; logname= uid=0 euid=0 tty=ssh ruser= rhost=116.31.116.10  user=root
root@regru:~#