ssh-agent: How to set it up so my CentOS server will only ask for passphrase once? On my Macbook, my SSH private key is encrypted, but I never have to re-enter the passphrase even if I reboot the machine. The system must be unlocking it along with my user account. Is it possible to set it up the same way for my user account on a CentOS server? There should be some sort of option that would basically encrypt the privatekey with the user account password (or at least encrypt the passphrase with the user password). I do not want the private key in plaintext on the hard disk, and would prefer not to have to enter many passwords. If the answer is no, then I probably will need to enter it once each time the server is booted. That is less good, but since that should be a rare occurrence, that would be tolerable.

You need a keyring or keychain to maintain the ssh-agent auth socket location for you.

On CentOS you can install keychain, see < for a detail guide on how to setup keychain on CentOS.