Ubuntu – How to repair gnome-keyring to unlock the SSH keys automatically after login

I think what you're really looking for is keychain, which is similar to the ssh-reagent you mention. Once configured in your .bashrc it'll prompt for the passphrase of the key(s) you asked it to manage only when you launch the first terminal after login and makes sure every new terminal knows about your ssh-agent.

1) After Creating the Public Key By Following,

The first step involves creating a set of RSA keys for use in authentication. This should be done on the client. To create your public and private SSH keys on the command-line:

mkdir ~/.ssh
chmod 700 ~/.ssh
ssh-keygen -t rsa

You will be prompted for a location to save the keys, and a passphrase for the keys. This passphrase will protect your private key while it's stored on the hard drive and be required to use the keys every time you need to login to a key-based system:

Generating public/private rsa key pair.
Enter file in which to save the key (/home/b/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/b/.ssh/id_rsa.
Your public key has been saved in /home/b/.ssh/id_rsa.pub.

2) You must add your private key (might be not secure) but still you can do this,

ssh-add ~/.ssh/id_rsa

Source From Ubuntu Wiki.