This is a only version

Found at: raymii.org:70/Keepalived_notify_script_execute_action_on_failover.txt

This is a text-only version of the following page on https://raymii.org:
Title       : 	Keepalived notify script, execute action on failover
Author      : 	Remy van Elst
Date        : 	26-10-2014
URL         : 	https://raymii.org/s/tutorials/Keepalived_notify_script_execute_action_on_failover.html
Format      : 	Markdown/HTML
Keepalived supports running scripts on VRRP state change. This can come in handy
when you need to execute an action when a failover occurs. In my case, I have a
VPN running on a Virtual IP and want to make sure the VPN only runs on the node
with the Virtual IP.

I'm developing an open source monitoring app called Leaf Node Monitoring, for windows, linux & android. Go check it out!

Consider sponsoring me on Github. It means the world to me if you show your appreciation and you'll help pay the server costs.

You can also sponsor me by getting a Digital Ocean VPS. With this referral link you'll get $100 credit for 60 days.

If you want to set up a simple keepalived cluster, see [my tutorial on that][2].
The VPN uses `strongswan` and is a simple ipsec site to site VPN. The two nodes
are datacenter redundant. The nodes function as NAT/firewall proxies for a
backend network. The backend servers need access to some other servers only
reachable over the VPN.
A notify script can be used to take actions, not only removing or adding an IP
to an interface. It can for example start or stop a daemon, depending on the
VRRP state.
It is defined in the keepalived config like this:
    vrrp_instance Example_VRRP {
        notify /usr/local/sbin/notify-keepalived.sh
The script can be written in any language as long as it is executable. It
receives the following parameters:
  * $1 = "INSTANCE" or "GROUP"
  * $2 = name of instance or group
  * $3 = target state of transition, "MASTER", "BACKUP" or "FAULT"
This is the bash script I use for the strongswan VPN:
    case $STATE in
            "MASTER") /usr/sbin/service strongswan start
            "BACKUP") /usr/sbin/service strongswan stop
            "FAULT")  /usr/sbin/service strongswan stop
                      exit 0
            *)        /sbin/logger "ipsec unknown state"
                      exit 1
   [1]: https://www.digitalocean.com/?refcode=7435ae6b8212
   [2]: https://raymii.org/s/tutorials/Keepalived-Simple-IP-failover-on-Ubuntu.html
All the text on this website is free as in freedom unless stated otherwise. 
This means you can use it in any way you want, you can copy it, change it 
the way you like and republish it, as long as you release the (modified) 
content under the same license to give others the same freedoms you've got 
and place my name and a link to this site with the article as source.
This site uses Google Analytics for statistics and Google Adwords for 
advertisements. You are tracked and Google knows everything about you. 
Use an adblocker like ublock-origin if you don't want it.
All the code on this website is licensed under the GNU GPL v3 license 
unless already licensed under a license which does not allows this form 
of licensing or if another license is stated on that page / in that software:
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    GNU General Public License for more details.
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see .
Just to be clear, the information on this website is for meant for educational 
purposes and you use it at your own risk. I do not take responsibility if you 
screw something up. Use common sense, do not 'rm -rf /' as root for example. 
If you have any questions then do not hesitate to contact me.
See https://raymii.org/s/static/About.html for details.