Centos/RedHat Server password less authentication
First Login to your Server
Generate Authentication keys
Authentication key cmds
[root@rserver8 ~]# ssh-keygen
Once you had executed the command
So, authorized keys are generated go to ~/.ssh/ directory or cd .ssh/
2 keys had generated
Id_rsa and id_rsa.pub
Using cat cmd display id_rsa.pub keys
[root@rserver8 .ssh]# cat id_rsa.pub
Copy this key
Create new authorized_keys file
So, using vi or vim cmd we can create
[root@rserver8 .ssh]# vi authorized_keys
Paste it here id_rsa.pub keys which you have copied using cat id_rsa.pub
Chmod 600 sets permissions so that, user / owner can read, can write and can’t execute. Group can’t read, can’t write and can’t execute. others can’t read, can’t write and can’t
So, I had created the authorized_keys now assign the permission to this particular user
So in my case root is the owner you can create user and assign the privileges
[root@rserver8 .ssh]# chmod 600 authorized_keys
So, now need to copy private key
Again, go to .ssh folder
[root@rserver8 ~]# cd .ssh/
[root@rserver8 .ssh]# cat id_rsa
Copy this and paste it to any text editor
And save it to .ppk format
PuTTY Private Key
…
Now to to ssh_config and disable password authentication login
And if you are using any user you can also disable root login
[root@rserver8 .ssh]# vi /etc/ssh/sshd_config
password authentication change it make it no.
So, once authentication done restart the sshd services (Secure Shell or Secure Socket Shell).
[root@rserver8 .ssh]# sudo systemctl restart sshd
I am saving private key in notepad text editor .ppk format
So here we need to convert in putty format if we don’t do it, we will get the error.
Go to ssh tab and browse the .ppk save private here we will get error because we are not using putty format
If you can check getting the format error
Now open the putty generator
Once file .ppk is loaded save it to same format with new or existing name
Click to save private key
And click yes
And save it
Now open the putty type username like sharique@192.168.60.10
Browse the authenticate key
Open the putty for remember login
So, Now you have successfully configured password less authentication Linux server.