This is the series of How to build / install / create an Elrond Node, either on Mainnet, Testnet or Devnet.
Part 06 – Disabling the password availability for connecting via SSH

INSTRUCTIONS:

Make Sure You Can Connect To The Server Using The New Port # & SSH Private Key:

1. if you can connect via ssh using putty, solar-putty, etc (just make sure you delete the previous connection settings and restart the applications to clear up the cache memory) to theNewUserNameHere at theServerIpAddressHere but WITHOUT using the password (just the using these 5 elements: theNewPortNumber + theNewUserNameHere + theServerIpAddressHere + the private ssh key file + the passphrase for the private ssh key) because it just logs in because of the ssh private key, THEN AND ONLY THEN you can get in and remove password authentication allowance when connecting via ssh with theNewUserNameHere by doing step 2 from Point 5 as follows:
2. open the sshd_config file: sudo nano /etc/ssh/sshd_config
3. then change this line # PasswordAuthentication yes to PasswordAuthentication no
4. save the file with CTRL+x — type y — hit Enter
5. restart the ssh server/daemon for all these to have effect like this: sudo service ssh restart