Category Archives: computing

SSH login without password

I’ll set this up once or twice each year. And every time something will go wrong and I’ll have to read the instructions from several sources again and again. I just did all that again. So, I’m going to write down the steps for future reference:

1. user@client$ ssh-keygen -t rsa  # use empty passphrase
2. user@client$ cat .ssh/ | ssh user@server 'cat >> .ssh/authorized_keys'  # .ssh directory must exist in server.
3. user@server$ chmod 600 $HOME/.ssh/authorized_keys
4. user@server$ chmod 700 $HOME/.ssh
5. user@server$ chmod 755 $HOME  # Make sure the home directory is not group/other writable.

Now, user can login to server from client without password.