autossh config

~# vim /etc/systemd/system/autossh.service

[Unit]
Description=Keeps some tunnels to '***.host-h.net' & '***.host-h.net' open
After=network-online.target

[Service]
# User=autossh
# -p [PORT]
# -l [user]
# -M 0 --> no monitoring
# -N Just open the connection and do nothing (not interactive)
# LOCALPORT:IP_ON_EXAMPLE_COM:PORT_ON_EXAMPLE_COM
ExecStart=/usr/bin/autossh -M 0 -o "ServerAliveInterval 60" -o "ServerAliveCountMax 3" -p 55 -l roland ****.za.net -NfL 222:****.host-h.net:22 -i /root/.ssh/id_rsa

[Install]
WantedBy=multi-user.target

root@s1:~# systemctl restart autossh
root@s1:~# systemctl status autossh
● autossh.service - Keeps some tunnels to 'ftpbackup5.jnb1.host-h.net' & 'ftpbackup2.jnb1.host-h.net' open
   Loaded: loaded (/etc/systemd/system/autossh.service; disabled)
   Active: inactive (dead)

Jul 19 20:55:51 s1 autossh[14588]: starting ssh (count 1)
Jul 19 20:55:51 s1 autossh[14588]: ssh child pid is 14589
Jul 19 20:59:39 s1 systemd[1]: Starting Keeps some tunnels to 'ftpbackup5.jnb1.host-h.net' & 'ftpbackup2.jnb1.host-h.net' open...
Jul 19 20:59:39 s1 systemd[1]: Started Keeps some tunnels to 'ftpbackup5.jnb1.host-h.net' & 'ftpbackup2.jnb1.host-h.net' open.
Jul 19 20:59:39 s1 systemd[1]: autossh.service: main process exited, code=exited, status=217/USER
Jul 19 20:59:39 s1 systemd[1]: Unit autossh.service entered failed state.
Jul 19 21:28:46 s1 systemd[1]: Starting Keeps some tunnels to 'ftpbackup5.jnb1.host-h.net' & 'ftpbackup2.jnb1.host-h.net' open...
Jul 19 21:28:46 s1 systemd[1]: Started Keeps some tunnels to 'ftpbackup5.jnb1.host-h.net' & 'ftpbackup2.jnb1.host-h.net' open.
Jul 19 21:28:46 s1 autossh[22116]: starting ssh (count 1)
Jul 19 21:28:46 s1 autossh[22116]: ssh child pid is 22117
Jul 19 21:29:47 s1 systemd[1]: Starting Keeps some tunnels to 'ftpbackup5.jnb1.host-h.net' & 'ftpbackup2.jnb1.host-h.net' open...
Jul 19 21:29:47 s1 systemd[1]: Started Keeps some tunnels to 'ftpbackup5.jnb1.host-h.net' & 'ftpbackup2.jnb1.host-h.net' open.

root@s1:~# netstat -tunap | grep 222
tcp        0      0 192.168.121.33:45222    192.168.121.33:6789     ESTABLISHED 3067/ceph-osd
tcp        0      0 192.168.121.33:6803     192.168.121.33:35222    ESTABLISHED 2919/ceph-osd
tcp        0      0 192.168.121.33:35222    192.168.121.33:6803     ESTABLISHED 3884/ceph-osd
tcp        0      0 192.168.121.33:6789     192.168.121.33:45222    ESTABLISHED 2783/ceph-mon
root@s1:~# ps ax | grep ssh
  324 ?        Ss     0:00 sshd: root@pts/2
  653 tty1     S+     0:01 ssh 192.168.121.30
 2563 ?        Ss     0:00 /usr/sbin/sshd -D
 6415 ?        Ss     0:00 /usr/sbin/sshd
14815 ?        Ss     0:00 /usr/sbin/sshd -D
23722 pts/2    S+     0:00 grep ssh

root@s1:~# tail /var/log/syslog
Jul 19 21:28:46 s1 autossh[22116]: starting ssh (count 1)
Jul 19 21:28:46 s1 autossh[22116]: ssh child pid is 22117
Jul 19 21:28:46 s1 systemd[1]: Failed to reset devices.list on /system.slice/system-ceph\x2dmon.slice: Invalid argument
Jul 19 21:28:46 s1 autossh[22116]: received signal to exit (15)
Jul 19 21:29:47 s1 systemd[1]: Starting Keeps some tunnels to 'ftpbackup5.jnb1.host-h.net' & 'ftpbackup2.jnb1.host-h.net' open...
Jul 19 21:29:47 s1 systemd[1]: Started Keeps some tunnels to 'ftpbackup5.jnb1.host-h.net' & 'ftpbackup2.jnb1.host-h.net' open.
Jul 19 21:29:47 s1 autossh[22343]: port set to 0, monitoring disabled
Jul 19 21:29:47 s1 autossh[22347]: starting ssh (count 1)
Jul 19 21:29:47 s1 autossh[22347]: ssh child pid is 22348
Jul 19 21:29:47 s1 autossh[22347]: ssh exited on signal 15; parent exiting

root@s1:~# journalctl -x -u autossh
... (showing only the lines from the last restart)
Jul 19 21:48:34 s1 systemd[1]: Started Keeps some tunnels to 'ftpbackup5.jnb1.host-h.net' & 'ftpbackup2.jnb1.host-h.net' open.
-- Subject: Unit autossh.service has finished start-up
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit autossh.service has finished starting up.
--
-- The start-up result is done.
Jul 19 21:48:34 s1 autossh[26635]: starting ssh (count 1)