It is possible to ssh from one Linux or Mac machine to another Linux server by using only cryptographic keys instead of using a password.
Create the private key on the source computer
On the source system
192.168.100.1 create the private key with the following command:
Choose no passphrase when asked and accept the default filename of id_rsa. This creates both the
id_rsa private key file and a
id_rsa.pub public key file. Keep the private key on the source system and copy the public key to the destination system.
Move the public key to the destination computer
Now we need the move that public key from the source computer to the destination.
From the source
192.168.100.1 use the following command:
This is the username you normally use to ssh into that system. So if your username was
darcy and the destination IP is
192.168.200.1 then the command becomes:
Congrats you’ve set up the ssh keys so that you no longer need to use a password when ssh’ing into that system. To test this simply do ssh like normal and it should automatically connect you.
Add an alias
You can add an alias for this command to make it even quicker to get to that system. If you’re using a bash shell simply add this to your .bashrc file on your source computer.
Now you simply need to type
s1 and you’ll automatically be logged into that system.
Verify you have spelled the
authorized_keys file correctly.
Sometimes permissions needs to be set on the directory and file. Here are the permissions needed to be set.