I have read an article about SSH passphrases (github:help), but they only explain how to use ssh-agent with msysgit and Mac OSX, no word about Linux.

This guide is about how to use KDE Wallet with ssh-agent. This way, we can use SSH keys with passphrases, but we don't need to enter a passphrase every time we use the key, KDE Wallet does the job. I assume you are using KDE.

In 3 easy steps:

1. Install ksshaskpass

Use your favorite package manager. You can use the script at the end of the page to automate the remaining steps Link

2. Create script file

Create the file

~/.kde/Autostart/ssh-add.sh

On some distributions ~/.kde4/Autostart/ssh-add.sh

And add this content

#!/bin/sh
export SSH_ASKPASS=/usr/bin/ksshaskpass
ssh-add < /dev/null

3. Make it executable

chmod +x ~/.kde/Autostart/ssh-add.sh

And run the script (or restart the session)

Extra

For security reasons, is a good idea stop ssh-agent when you finish your session, create the file

~/.kde/shutdown/ssh-agent.sh

With this content

#!/bin/sh
ssh-agent -k

This file should be executable

Script to copy the files automatically

wget http://japeto.com/scripts/set_files_ssh_agent.sh && sh set_files_ssh_agent.sh

A good page for more info about SSH: Secure Shell (Arch Linux)