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1 vote
Current Version
Last Release Date
Compatible With
  • Nagios 1.x
  • Nagios 2.x
  • Nagios 3.x
  • Nagios 4.x
  • Nagios XI
Network Monitoring Software - Download Nagios XI
Log Management Software - Nagios Log Server - Download
Netflow Analysis Software - Nagios Network Analyzer - Download
This plugin checks your Server for banned IPs by fail2ban.
### Installation
This plugin requires fail2ban and sudo installed. Also several commands must be runnable by nagios user with sudo, so add the following to visudo:

# Needed for check_fail2ban
nagios ALL=NOPASSWD: /usr/bin/fail2ban-client status
nagios ALL=NOPASSWD: /usr/bin/fail2ban-client status *
nagios ALL=NOPASSWD: /usr/bin/fail2ban-client get * banip
nagios ALL=NOPASSWD: /usr/bin/fail2ban-client get * banip --with-time
nagios ALL=NOPASSWD: /usr/bin/fail2ban-client get * bantime
### Usage
./check_fail2ban -h Display this message
-w defaults to 10
-c defaults to 20
-t Time: Display until when IPs will be banned
-j i.e. comma separated string of jails, i.e. ssh,postfix
Only check those jails
./check_fail2ban -t -w 5 -c 10 -j ssh,postfix
./check_fail2ban -t
Reviews (1)
H, thank you for this plugin,. It works great when I run it locally on the machine where Fail2Ban is running. But I cannot get it running remotely from the Nagios Server.

I tried to check it directly with adding "-H " to your command syntax as well as configure a remote NRPE call from Nagios Server to the server where Fail2Ban is running. But the result is still the same: "Error: fail2ban-client not found"

What do I do wrong? Thank you, Jakub
Owner's reply

Hi, sorry for the late response!
it is intended to run this command via NRPE from the nagios server. Are you sure that your nrpe command is defined properly? How does it look like?