To use SSH keys instead of plain password to login:
1. Logon to WHM and go to Main >> Security >> Security Center
2. Under “SSH Password Auth Tweak” and disable the Password Authentication.
3. Under “Manage SSH Keys” click on Generate new key.
4. Give a Key name and Generate a good password (remember it). Choose KeyType as DSA since it’s more secure than RSA.

5. Once done, you will see a pair of public private keys. Authorize the public key to connect.
6. View/Download the private key to your system. If you’re using putty it can also generate in relevant format.
7. Save the key in a secure place in your local system and chmod to 600 so that no one can read it.
8. Next, connect to your server

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root@localhost ~]# ssh -i /path-to-file/file.key root@server.ip.address
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If you require help, contact SupportPRO Server Admin