SSH(oh)				     LOCAL			       SSH(oh)

ssh - usage, configuration and tips

SYNOPSIS
	   ssh [OPTION] REMOTE_HOST [COMMAND]

TOC
	   COMMAND LINE
	   - options
	   - x forwarding
	   TUNNEL
	   - create
	   - connect through vpn on ssh tunnel
	   - commands
	   CONFIGURATION
	   - example
	   - control master
	   SSH KEYS
	   TODO
	   SEE ALSO

COMMAND LINE
   options
     -f			  : fork
     -L			  : local forward
     -D			  : dynamic forward

   x forwarding
     -	 does not work on slackware
	       ssh -X
     -	 trusted, works on debian/slackware
	       ssh -Y

TUNNEL
   create
     Example: This can be used to create a socks proxy for a browser.
	   ssh -f -D $PORT $SERVER sleep 30000
     -	 D bindaddres:port / port (assumes localhost)
     -	 sleep 30000 : keep the connection alive with sleep command

   connect through vpn on ssh tunnel
     Example: If a SQL Server is only accesible in a different network, a
     tunnel can be created to access the SQL server through a computer that is
     accessible from outside that network.

   commands
	   ssh -f -L 127.0.0.1:$PORT:$TARGET_SERVER:$TARGET_PORT
	   $SSH_SERVER_USR@$SSH_SERVER sleep 30000
	   ssh -f -L 127.0.0.1:1234:SQL_server:1433 user@ssh_server sleep
	   30000
	     NOTE: on Microsoft SQL Server Studio use 127.0.0.1,1234

CONFIGURATION
     To add configuration options for specific host:
     $HOME/.ssh/config
     Host hostname
	      [SSH OPTION]

   example
     This will always use port 8686 to connect to hostname:
     Host hostname
	     Port 8686

   control master
	     NOTE: The user needs to have write permissions in the directory
	     where the socket will be created.
     Create a persistent connection when connecting to a remote machine. Eg.:
	   ssh -f remote sleep 30
     Host [HOST]
	     ControlMaster auto
	     ControlPersist yes
	     ControlPath [PATH_TO_CONTROL_SOCKET]/%r@%h:%p

   Commands
     The socket can be controlled using -O: ssh -O
     [stop|exit|cancel|check|forward|proxy] HOST

     stop   | stop accepting requests.
     exit   | exit master.
     cancel | cancel forwardings.
     forward
	    | request forwardings.
     proxy  | connect to master in proxy mode.

SSH KEYS
	   ssh-keygen
     Copy the resulting pub contents to the corresponding Host.

TODO
     -	 Review -L.
     -	 Add better examples.

SEE ALSO
     - OpenBSD manpages: ssh(1) , ssh_config(8) , sshd_config(8)

AUTHORS
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     <admin@ohazot.com>

OpenBSD 7.7 linux|  Created:2025-10-03|Updated:2025-10-19|	       SSH(oh)