How to configure and use multiple ssh RSA keys with Keychain help I am looking for a solution that would automatically load multiple RSA keys at login, some of them having passwords stored in the Keychain.

Example: first keys would be obviously in ~/.ssh/id_rsa and let's say that the second cone would be in ~/.ssh/id_rsa.2.

I want them to be loaded automatically, without having to enter their passwords.
ssh-agent can do this: use ssh-add -K path/to/key to store the passphrase for the key in your Keychain. Whenever you do something requiring that key you won't be prompted for your password, provided the Keychain is unlocked.

This article gives more information, as does this related ServerFault question.