FreeBSD-11.1p10 and autossh

[Dave Cottlehuber]

On Thu, 14 Jun 2018, at 17:27, James B. Byrne via freebsd-questions wrote:> I cannot seem to configure autossh to work from anything other than
> the command line, which defeats the purpose. I would like it to
> automatically start when the system boots but I have been unsuccessful> in all my attempts to date. I have tried adding this in rc.conf:
>
> autossh -M0 -f -i /root/.ssh/id_ed25519 -L 143:localhost:143
> root at 192.168.216.17
>
> But there is no evidence that this even gets executed.  In any case it> is not running after a restart and no error messages are logged.
>
> I created a primitive rd.d script which runs but which does not
> establish a link between the systems.  ps reports that autossh is
> running and that it is the parent of a process pid.  But that pid does> not exist and there is nothing logged anywhere that I can find to show> that it ever did.
>
> The options that I pass from rc.conf to the rc.d/autossh script are:
>
> autossh_enable="YES"              # enable autossh
> autossh_flags='-M0 -f \
>   -i "/root/.ssh/id_rsa" \
>   -o "ServerAliveInterval 30" \
>   -o "ServerAliveCountMax 3" \
>   -L "143:localhost:143" \
>   -N \
>      "root at 192.168.216.17"'
>
> This starts autossh as shown below:
>
>  ps -auxw | grep ssh
> root      2971  0.0  0.0   8332   1640  -  SsJ  10:52   0:00.00
> autossh: parent of 33977 (8) (autossh)
> root     13736  0.0  0.1  57812   4856  -  SsJ  10:52   0:00.00
> /usr/sbin/sshd
> root     32028  0.0  0.1  85228   5620  -  SsJ  10:52   0:00.02 sshd:> root at pts/1 (sshd)
> root     34983  0.0  0.0  14828   1804  1  S+J  10:52   0:00.00 grep
> --color ssh
>
>
> But there is no connection to the remote host.  If I run autossh from> the command line with the same options then I see this:
>
> autossh -M0 -f   -i "/root/.ssh/id_rsa"   -o "ServerAliveInterval 30">  -o "ServerAliveCountMax 3"   -L "143:localhost:143"   -N    
> "root at 216.185.71.17"&
>
>
> ps -auxw | grep ssh
> . . .
> root     53110  0.0  0.0   8332   1700  -  IsJ  10:56   0:00.00
> autossh: parent of 53777 (1) (autossh)
> root     53777  0.0  0.1  24580   4380  -  SJ   10:56   0:00.03
> /usr/bin/ssh -i /root/.ssh/id_rsa -o ServerAliveInterval 30 -o Serv
> . . .
>
>
> The rc.d script is very basic and contains this:
>
>
> source /etc/rc.subr
>
> name="autossh"
> rcvar=autossh_enable
>
> load_rc_config $name
>
> : ${autossh_enable:="NO"}
> : ${autossh_pidfile:="/var/run/autossh.pid"}
> : ${autossh_procname:="/usr/local/bin/autossh"}
>
> start_cmd=${name}_start
> stop_cmd=${name}_stop
>
> pidfile=${autossh_pidfile}
> procname=${autossh_procname}
>
> autossh_start() {
>  AUTOSSH_PIDFILE=${autossh_pidfile} ${autossh_procname}
>  ${autossh_flags}>   AUTOSSH_DEBUG=7
>   AUTOSSH_LOGLEVEL=7
>   AUTOSSH_LOGFILE="/var/log/autossh.log"
> }
> autossh_stop() {
>  kill -9 "$(cat ${AUTOSSH_PIDFILE})";
>  rm -f "${AUTOSSH_PIDFILE}"
> }
> run_rc_command "$1"
>
> But this does not work as I expect either.  fROM THE CLI 'service
> autossh start' runs autossh but autossh does not establish an ssh
> connection to the target. The pid autossh claims to be the parent of
> does not exist when I search for it using ps.  Despite the debugging
> and logging settings nothing appears in the autossh logfile.  There is> nothing in /var/log/auth.log on the target host to indicate that an
> ssh connection is even attempted.
>
> This is more of an annoyance than anything else but I am mystified
> that something as basic as this just will not run as I expect.  Why
> does autossh work as expected when started from the command line but

I highly recommend spiped https://www.freshports.org/sysutils/spiped/
and leave autossh in the dust where it belongs. It has an rc.d script
and is robust against failure.
A+
Dave