OS X¶

Tunneling a MySQL database with SSH¶

In General: Tunneling a remote port to a local port¶

Goal¶

I have a MySQL database in a remote customer server or a local Vagrant box. I want to access it with my tools as if it is a database of the local OS X machine 127.0.0.1:33333. This can be done in a secure way by tunneling it with SSH.

Scenario¶

Assume the following setup is given¶

Remote password:
Remote host:	192.168.56.2 (the Vagrant box)
Remote user:	vagrant
	vagrant
DB IP inside remote host:
	127.0.0.1
DB port inside remote host:
	133006
DB user:	dev
DB password:	dev

Wanted¶

Local IP:	127.0.0.1 (localhost)
Local Port:	33333

Solution¶

I dig the SSH tunnel like this.

ssh -L 127.0.0.1:33333:127.0.0.1:13306 vagrant@192.168.56.2  -N

Now I can access the DB like wanted.

mysql --host=127.0.0.1 --port=33333 --user=dev --password=dev

Use CTRL-C to terminate the tunnel.

Tip

As it is hard to memorize, I also set up an alias.

alias dbtunnel="ssh -L 127.0.0.1:33333:127.0.0.1:13306 vagrant@192.168.56.2  -N"

Explanation¶

The parameter -L specifies the link. The first part is the local one, the second part the remote.

The parameter -N instructs not to open the ssh shell.

Manpage SSH:

-L      [bind_address:]port:host:hostport
        Specifies that the given port on the local (client) host is to be
        forwarded to the given host and port on the remote side.  This
        works by allocating a socket to listen to port on the local side,
        optionally bound to the specified bind_address.  Whenever a connec-
        tion is made to this port, the connection is forwarded over the
        secure channel, and a connection is made to host port hostport from
        the remote machine.  Port forwardings can also be specified in the
        configuration file.  IPv6 addresses can be specified by enclosing
        the address in square brackets.  Only the superuser can forward
        privileged ports.  By default, the local port is bound in accor-
        dance with the GatewayPorts setting.  However, an explicit
        bind_address may be used to bind the connection to a specific
        address.  The bind_address of ``localhost'' indicates that the lis-
        tening port be bound for local use only, while an empty address or
        `*' indicates that the port should be available from all inter-
        faces.

-N      Do not execute a remote command.  This is useful for just forward-
        ing ports (protocol version 2 only).