Apr 12, 2018 SSH-key-based authentication provides a more secure alternative to password-based authentication. In this tutorial we'll learn how to set up SSH-key-based authentication on a CentOS 7 installation. When I clone an OS image to a new, identical hardware PC I of course need to change the host name in a couple of places on the new machine. I suspect it is also good practice to generate new ssh keys for use by openssh server. . Normally this happens when SSH keys don’t get generated on the startup. If your system is compromised and your keys are stolen and you want to generate new keys. There could be some other reasons also but if you are reading this article then i believe you already have some reason with you. Generating Host Keys.

1. Generate Ssh Key Centos 7
2. Generate A New Ssh Key Centos Download
3. Centos Ssh Authorized Keys
4. Generate A New Ssh Key Centos Download

Here is a short note on configuring passwordless logins between 2 Linux systems. Process basically involves generating a public authentication key and appending it to the remote hosts ~/.ssh/authorized_keys file.

Generate authentication key

If an SSH authentication-key file does not exist, generate one by running the ssh-keygen command. When prompted for a passphrase, use a blank passphrase if fully password-less login is required:

Copy the public key to remote host

Use the ssh-copy-id command to install the public half of the newly-generated authentication key into a specific user’s home directory on the remote host. The ssh-copy-id command will then automatically append the identity information into the ~/.ssh/authorized_keys file for the specified user on the remote host (creating ~/.ssh and~/.ssh/authorized_keys if necessary).

Alternatively if the server is not installed with openssh-clients (a package which provides ssh-copy-id command utility) you can copy the authentication key with the command:

If everything is configured right, you should be able to login into to the remote host without password.

Generate Ssh Key Centos 7

Troubleshooting

Check for the correct permissions

Generate A New Ssh Key Centos Download

The most common cause of problems with getting key-based ssh authentication to work is file permissions on the remote ssh server
If the above steps were followed and ssh’ing to the appropriate user is still prompting for passwords, inspect the permissions on both the local and remote user’s files. /online-key-generator-gta-v.html. The permissions of the directories should be exactly as show below. The example shown here is for the user “oracle”

If the permissions are not as show abover, set them correct :

Centos Ssh Authorized Keys

Restart the sshd service for the changes to take effect :

Generate A New Ssh Key Centos Download

disabling SElinux

SELinux can also potentially prevent sshd from accessing the ~/.ssh directory on the server. This problem can be ruled out (or resolved) by running restorecon as follows on the remote user’s ~/.ssh directory: