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.
2. Create script file
Create the file
On some distributions ~/.kde4/Autostart/ssh-add.sh
And add this content
3. Make it executable
And run the script (or restart the session)
For security reasons, is a good idea stop ssh-agent when you finish your session, create the file
With this content
This file should be executable
A good page for more info about SSH: Secure Shell (Arch Linux)