Assume that you are a user "aliceA" on hostA, and wish to ssh to hostB as user "aliceB", without entering her password on hostB. You can follow this guide to enable ssh login without entering a password.
First of all, you need to be logged in as user "aliceA" on hostA.
Generate a public/private rsa key pair by using ssh-keygen. The generated key pair will be stored in ~/.ssh directory.
Then, create ~/.ssh directory on aliceB account at the destination hostB by running the following command. This step can be omitted if there is already .ssh directory at aliceB@hostB.
Finally, copy the public key of user "aliceA" on hostA to aliceB@hostB to enable password-less ssh.
From this point on, you no longer need to type in password to ssh to aliceB@hostB from aliceA@hostA.
1. You are still asked for an SSH password even after enabling key authentication. In this case, check for system logs (e.g., /var/log/secure) to see if you see something like the following.
Authentication refused: bad ownership or modes for file /home/aliceB/.ssh/authorized_keys
In this case, failure of key authentication is due to the fact that the permission or ownership ~/.ssh/authorized_keys file is not correct. Typically this error can happen if ~/.ssh/authorized_keys is read accessible to anyone but yourself. To fix this problem, change the file permission as follows.
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