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I'm running yum installed autossh 1.4a on fedora core 15 with the latest updates.

This works:

ssh -L 9000:valid.fqdn:80 another_valid_fqdn

However, autossh fails and prints its usage message:

ssh -L 9000:valid.fqdn:80 another_valid_fqdn

usage: autossh [-V] [-M monitor_port[:echo_port]] [-f] [SSH_OPTIONS]

-M specifies monitor port. May be overridden by environment
   variable AUTOSSH_PORT. 0 turns monitoring loop off.
   Alternatively, a port for an echo service on the remote
   machine may be specified. (Normally port 7.)
-f run in background (autossh handles this, and does not
   pass it to ssh.)
-V print autossh version and exit.

Environment variables are: AUTOSSH_GATETIME - how long must an ssh session be established before we decide it really was established (in seconds) AUTOSSH_LOGFILE - file to log to (default is to use the syslog facility) AUTOSSH_LOGLEVEL - level of log verbosity AUTOSSH_MAXSTART - max times to restart (default is no limit) AUTOSSH_MESSAGE - message to append to echo string (max 64 bytes) AUTOSSH_PATH - path to ssh if not default AUTOSSH_PIDFILE - write pid to this file AUTOSSH_POLL - how often to check the connection (seconds) AUTOSSH_FIRST_POLL - time before first connection check (seconds) AUTOSSH_PORT - port to use for monitor connection AUTOSSH_DEBUG - turn logging to maximum verbosity and log to

Any ideas how I might get autossh to work? According to the usage message it should just take ssh options directly.

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Monitor port is not optional apparently. Try autossh -M 0 -L 9000:valid.fqdn:80 another_valid_fqdn –  AndreasM Feb 9 '12 at 16:29
@AndreasM That works! Thanks. Add it as an answer and I'll mark it answered. –  David Watson Mar 8 '12 at 17:48

1 Answer 1

up vote 3 down vote accepted

The monitor port is apparently not optional. Try autossh -M 0 -L 9000:host:80 ssh_host

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