The Problem
If you are sick of re-entering your SSH passphrase per login shell 😒…
eval $(ssh-agent -s )
ssh-add ~/.ssh/id_rsa
# re-enter passphrase
SSH-Agent:
Keychain will allow you to enter your SSH passphrase per system reboot, 😲
How???
Keychain will automatically re-use your pre-existing ssh-agent process and have instant access to any pre-loaded keys and passphrases.
Keychain:
**Keychain is just a front-end to ssh-agent
Summary of Steps
Below are the exact steps I took in the Keychain playlist.
You may have to adjust a few parameters to your environment but the Linux commands should be the same.
# Generate your SSH keypair (Public/Private)
# Public Key ends with a *.pub
# Private Key has no extension
ssh-keygen
# Copy Public Key to host(s)
ssh-copy-id -i /home/user1/.ssh/id_rsas.pub user1@remote1
# Test Private Key
ssh -i /home/user1/.ssh/id_rsa user1@remote1
#############################
#
# Legacy Method: NO KEYCHAIN
#
#############################
eval $(ssh-agent -s )
ssh-add /home/user1/.ssh/id_rsa
# View loaded keys
ssh-add -l
# Test "agent process"
ssh -i /home/user1/.ssh/id_rsa user1@remote1
#############################
#
# NEW Method: KEYCHAIN! 🙂
#
#############################
# Install keychain
sudo apt-get install keychain
#####################
# UPDATE: 01/12/2026
# Add the following to "~/.bashrc" and keychain will look
# for and use your pre-existing ssh-agent every time.
#####################
eval `keychain --eval --agents ssh /home/user1/.ssh/id_rsa`
# Test keychain
ssh user1@remote1
Keychain Concepts
Here I explain the concepts that make up ssh key authentication and keychain:
Demonstration
Here, I show you how to actually implement keychain:
Learn Linux 