Enable SSH Root Login on Ubuntu 22.04¶

By default, Ubuntu disables root login over SSH for security reasons. Enabling root login is strongly discouraged in production environments because it increases the attack surface. However, if you need it (e.g., for testing or internal use), follow these steps carefully.

Prerequisites:¶

Server running Ubuntu 22.04 LTS.
Access as a non-root user with sudo privileges.
SSH already installed and running.

Connect to your server using your regular user account:

ssh username@your_server_ip

2. Switch to the root user¶

Once logged in, elevate privileges:

sudo -i

You should now see the prompt as root@your_server:~#.

3. Edit the SSH configuration file¶

Open the SSH daemon config file:

nano /etc/ssh/sshd_config

Look for the following parameters and modify as needed:

PermitRootLogin Change from prohibit-password or no to:

PermitRootLogin yes

PasswordAuthentication Make sure it’s set to:

PasswordAuthentication yes

⚠️ Notes:

If lines are commented with #, remove the # before editing.
Using yes allows password login, which is less secure. A better alternative is PermitRootLogin prohibit-password with SSH keys.

4. Save and exit¶

In nano, press:

CTRL + O → Enter (save)
CTRL + X → Exit

5. Restart SSH service¶

Apply changes by restarting the SSH service:

systemctl restart ssh

Check service status:

systemctl status ssh

Make sure it shows active (running).

From your local machine, try connecting directly as root:

ssh root@your_server_ip

If you enabled password authentication, enter the root password when prompted.

Security Recommendations¶

Enabling root login directly over SSH is not recommended. To improve security:

Use SSH keys Generate a key pair on your local machine:
```
ssh-keygen -t ed25519
```
Copy it to the server:
```
ssh-copy-id root@your_server_ip
```
Then disable password authentication:
```
PasswordAuthentication no
```
Restrict SSH access Edit /etc/ssh/sshd_config:
```
AllowUsers root username
```
Change default SSH port In /etc/ssh/sshd_config:
```
Port 2222
```
(Don’t forget to allow the new port in your firewall).
Use a firewall (UFW or iptables) to limit SSH access. Example with UFW:

ufw allow 2222/tcp
ufw enable

✅ Now you should be able to log in as root via SSH, but consider disabling it once your task is complete for better security.