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The screen program, among other useful things, lets you keep an SSH session running even after you disconnect from SSH. Here’s how to use it.

SSH in.

ssh user@hostname.com

Once on the remote machine, set up a named screen:

screen -S myscreen

In another terminal, open another SSH connnection and start another screen:

screen -S mysecondscreen

You can see they are there by using, in either of the terminals,

screen -ls

This does NOT start screen, just lists the different screens.

You can now disconnect the SSH connections. When you reconnect, you can use

screen -r myscreen

or

screen -r mysecondscreen

to reconnect to the one you want.

Some easy ways to configure SSH to be a little more secure:

Edit /etc/ssh/sshd_config as root.

• Change the port (default is 22)
• Change “PermitRootLogin yes” to “PermitRootLogin no”
• AddUser username
• save and quit
• restart the ssh server: sudo /etc/init.d/ssh restart

More info here:
http://ubuntu-tutorials.com/2007/02/14/what-you-ought-to-know-about-securing-ssh/

Easy way to add public key of this machine to a remote machine:

ssh-copy-id -i ~/.ssh/id_dsa.pub root@fileserver01

More good info here:
http://ubuntu-tutorials.com/2007/02/05/unattended-ssh-login-public-key-ssh-authorization-ssh-automatic-login/

Step 1: SSH forwarding

First, forward the local port 3307 to 3306. That is, when you access the local port 3307, it will redirect it to port 3306 on the remote host.

ssh -fNg4 -L 3307:127.0.0.1:3306 user@hostname

-f sends SSH to the background
-g allows remote hosts to connect to local forwarded ports
-N don’t execute a remote command
-4 this was key! Forces IPv4. Kept getting “bind: Address already in use” errors because I didn’t have this.
-L the forwarding magic happens here . . . syntax is localport:localhost:remoteport

Step 2: Connect to mysql on port 3307

. . . which will redirect to port 3306 on remote host.

mysql -u root -h 127.0.0.1 -P 3307 -p

and you’re in!