# Disabling access to Linux using a password

If you are using SSH keys, disabling access to the server via password will be a useful additional security measure for you.

## Switching off via nano

Use the following command:

```
nano /etc/ssh/sshd_config
```

We get into the **sshd** config.

<figure><img src="/files/o8mUmPOcufmqrlD12R0X" alt=""><figcaption></figcaption></figure>

We find the string **PasswordAuthentication yes**

<figure><img src="/files/h9GRE6a69iOsra8ThCl5" alt=""><figcaption></figcaption></figure>

We need to remove the grid (**#**) so that the row becomes active. And then we change the value of **yes** to **no.**

<figure><img src="/files/uPSUeUImHnRhDqARUgsv" alt=""><figcaption></figcaption></figure>

Press **Ctrl + X**, enter **Y** to save.

Restarting the **SSH** service:

```
sudo service ssh restart
```

## Disconnection via sFTP

In the panel above the file manager, we need to erase the standard path **/root** and specify **/etc/ssh**

In this directory, we need to open the **sshd\_config** file.

We find the corresponding **PasswordAuthentication yes** string.

<figure><img src="/files/0b9AOFJLvbFy2YgNy6YA" alt=""><figcaption></figcaption></figure>

Remove the grid (**#**) so that the line becomes active. And then we change the value of **yes** to **no**.

<figure><img src="/files/9kKJqPd5jyX3H41I0nFd" alt=""><figcaption></figcaption></figure>

We save the file and send it to the server.

## Restarting the SSH service:

```
sudo service ssh restart
```

## Using an SSH key in sFTP

After enabling access only via **SSH key**, a problem may arise when connecting via **sFTP**, which is extremely simple to solve at the moment.

### FileZilla

Click on the Edit category and select Settings

Then select the **sFTP** page and click the Add **Key File** button.

Select the location and add the file.

The key has been added, now **FileZilla** will take it into account when trying to connect to servers.

### WinSCP

Click on the button to create a new connection:

A window opens. Here we specify the **IP address** of the server and the **Username**.

Use the More button under the Password line.

In the window that opens, select the **Authentication** section.

Add the **private key** and click **OK**.

We are trying to connect to the server.

The program requests the secret key code, we enter spacecore:

We have connected to the server!


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