SSH

To configure SSH initially.

In the command prompt, type the following:

ssh-keygen

By default, the system will save the keys to C:\Users\your_username/.ssh/id_rsa.
You’ll be asked to enter a passphrase. Hit Enter to skip this step.
The system will generate the key pair, and display the key fingerprint and a randomart image.
Open your file browser.
Navigate to C:\Users\your_username/.ssh.
You should see two files. The identification is saved in the id_rsa file and the public key is labeled id_rsa.pub. This is your SSH key pair.

SSH root login is disabled by default as a security feature

Open the /etc/ssh/sshd_config file with administrative privileges and change the following line:

nano /etc/ssh/sshd_config

FROM:
#PermitRootLogin prohibit-password
TO:
PermitRootLogin yes

Restart SSH service:

sudo systemctl restart ssh

Copy public key to server

The following command will copy the public key to the server.

ssh-copy-id user@remote-host

Now try to login with

ssh root@server

SSH config file

The config file helps to configure all the host details which facilitates the connection:

Here is a sample config:

Host targaryen
    HostName 192.168.1.10
    User daenerys
    Port 7654
    IdentityFile ~/.ssh/targaryen.key

Host tyrell
    HostName 192.168.10.20

Host martell
    HostName 192.168.10.50

Host *ell
    user oberyn

Host * !martell
    LogLevel INFO

Host *
    User root
    Compression yes

Having the config file saved in c:\users\username.ssh\config

You can ssh just by typing the hostname :

ssh targaryen

SSH

To configure SSH initially.

Allow password login

Copy public key to server

SSH config file