fail2ban

Fail2ban Input Plugin

The fail2ban plugin gathers the count of failed and banned ip addresses using fail2ban.

This plugin runs the fail2ban-client command which generally requires root access. Acquiring the required permissions can be done using several methods:

• Use sudo run fail2ban-client.
• Run telegraf as root. (not recommended)

Using sudo

You will need the following in your telegraf config:

[[inputs.fail2ban]]
  use_sudo = true

You will also need to update your sudoers file:

$ visudo
# Add the following line:
Cmnd_Alias FAIL2BAN = /usr/bin/fail2ban-client status, /usr/bin/fail2ban-client status *
telegraf  ALL=(root) NOEXEC: NOPASSWD: FAIL2BAN
Defaults!FAIL2BAN !logfile, !syslog, !pam_session

Configuration:

# Read metrics from fail2ban.
[[inputs.fail2ban]]
  ## Use sudo to run fail2ban-client
  use_sudo = false

Measurements & Fields:

• fail2ban
  • failed (integer, count)
  • banned (integer, count)

Tags:

• All measurements have the following tags:
  • jail

Example Output:

# fail2ban-client status sshd
Status for the jail: sshd
|- Filter
|  |- Currently failed: 5
|  |- Total failed:     20
|  `- File list:        /var/log/secure
`- Actions
   |- Currently banned: 2
   |- Total banned:     10
   `- Banned IP list:   192.168.0.1 192.168.0.2

fail2ban,jail=sshd failed=5i,banned=2i 1495868667000000000