---
title: IP address unban
template: docs
taxonomy:
    category: docs
routes:
  default: '/fail2ban'
---

**Fail2Ban** is an intrusion prevention software that protects computer servers against brute-force attacks. It monitors certain logs and will ban IP addresses that show brute-force-like behavior.

In particular, **Fail2Ban** monitors `SSH` connection attempts. After 5 failed SSH connection attempts, Fail2Ban will ban the IP address from connecting via SSH for 10 minutes. If this address fails several times, it might get banned for a week.

## Unban an IP address

To unblock an IP address, you must first access your server by some means (for example from another IP address or from another internet connection than the banned one).

Then, look at the **Fail2Ban’s log** to identify in which `jail` the IP address has been banned:

```bash
sudo tail /var/log/fail2ban.log
2019-01-07 16:24:47 fail2ban.filter  [1837]: INFO    [sshd] Found 11.22.33.44
2019-01-07 16:24:49 fail2ban.filter  [1837]: INFO    [sshd] Found 11.22.33.44
2019-01-07 16:24:51 fail2ban.filter  [1837]: INFO    [sshd] Found 11.22.33.44
2019-01-07 16:24:54 fail2ban.filter  [1837]: INFO    [sshd] Found 11.22.33.44
2019-01-07 16:24:57 fail2ban.filter  [1837]: INFO    [sshd] Found 11.22.33.44
2019-01-07 16:24:57 fail2ban.actions [1837]: NOTICE  [sshd] Ban 11.22.33.44
2019-01-07 16:24:57 fail2ban.filter  [1837]: NOTICE  [recidive] Ban 11.22.33.44
```

Here, the `11.22.33.44` IP address has been banned in the `sshd` and `recidive` jails.

Then deban the IP address with the following commands:

```bash
sudo fail2ban-client set sshd unbanip 11.22.33.44
sudo fail2ban-client set recidive unbanip 11.22.33.44
```

## Whitelist an IP address

If you don’t want a "legitimate" IP address to be blocked by **YunoHost** anymore, then you have to fill it in the whitelist of the `jail` configuration file.

When updating the **Fail2Ban** software, the original `/etc/fail2ban/jail.conf` file is overwritten. So it is on a new dedicated file that we will store the changes. They will thus be preserved over time.

1. Start by creating the new jail configuration file which will be called `yunohost-whitelist.conf`:

    ```bash
    sudo touch /etc/fail2ban/jail.d/yunohost-whitelist.conf
    ```

2. Edit this new file with your favorite editor:

    ```bash
    sudo nano /etc/fail2ban/jail.d/yunohost-whitelist.conf
    ```

3. Paste the following content into the file and adapt the IP address `XXX.XXX.XXX.XXX`:

    ! Keep the `127.0.0.1/8`, it corresponds to the server [internal communication system](https://en.wikipedia.org/wiki/Localhost)

    ```bash
    [DEFAULT]

    ignoreip = 127.0.0.1/8 XXX.XXX.XXX.XXX
    #                      ^ Add your IP address or DNS host here
    #                        you can put more than one, separated by a space
    ```

4. You should get end up with something like this if you have added two ip addresses (ipv4 and [ipv6](/ipv6))

    ```bash
    [DEFAULT]

    ignoreip = 127.0.0.1/8 203.0.113.4 2001:DB8::1
    ```

5. **Save** the file and **reload** the Fail2Ban configuration:

    ```bash
    sudo fail2ban-client reload
    ```

6. **Check** that the configuration has been applied as expected:

    1. You should have this result

        ```bash
        root@sambain:/etc/nginx# fail2ban-client get sshd ignoreip
        These IP addresses/networks are ignored:
        |- 127.0.0.0/8
        |- 2001:db8::1
        |- XXX.XXX.XXX.XXX
        `- 203.0.113.4
        ```

    2. If there is an **error** with your change, you could end up with something like this:

        ```bash
        sudo fail2ban-client get sshd ignoreip
        These IP addresses/networks are ignored:
        |- 127.0.0.0/8
        |- #<=
        |- the
        |- IP
        |- address
        |- (you
        |- can
        |- put
        |- more
        |- than
        |- one
        |- separated
        |- by
        |- a
        |- space)
        |- that
        |- you
        |- want
        |- to
        |- whitelist
        |- 203.0.113.4
        |- XXX.XXX.XXX.XXX
        `- 2001:db8::1
        ```

        And you will need to fix it or revert your changes as Fail2ban could fail

        > For the curious, it was because of a [comment ;](https://github.com/fail2ban/fail2ban/blob/master/config/jail.conf#L30)

Congratulations, no more risks of banning yourself from your own YunoHost server!