Maybe this would help: <a href="http://onlamp.com/onlamp/2006/05/25/self-healing-networks.html">http://onlamp.com/onlamp/2006/05/25/self-healing-networks.html</a> <div class="gmail_quote">On Thu, Dec 10, 2009 at 3:08 PM, Christopher McAtackney <<a href="mailto:cristoir@gmail.com">cristoir@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Hi all, I have a need to control an Active / Passive pair of components and was wondering if anyone had tackled this problem with Nagios? The scenario is as follows; Host A has SERVICE_1 installed and running. Host B has SERVICE_2 installed, but not running. The desired functionality is to detect when SERVICE_1 is not running (or that Host A is down / unreachable), and then to start SERVICE_2 on Host B. I believe I can do this with Nagios by defining an event handler on SERVICE_1 which will make the appropriate call to start SERVICE_2 on Host B Would it make sense to store the relationship between SERVICE_1 and Host B / SERVICE_2 as a service macro, e.g. $_SERVICE_PASSIVE_HOSTNAME, $_SERVICE_PASSIVE_SERVICENAME? There are too many scenarios in which the SERVICE_1 might come back up to try automate the switching off of SERVICE_2 I believe, e.g. if someone pulled a network cable on Host A accidently, then plugged it in 15 minutes later - during which time Nagios detects that it is down and so starts up SERVICE_2. The user then plugs the network lead back in and now we have two Active instances running - which is what we specifically wanted to avoid. Even if Nagios detects that the primary component is up, it's still too late because any Active / Active overlap will cause problems for this particular application. I can't think of any way to automate that side of things - but does the general concept of having Nagios start up a Passive partner make sense? Thanks for any insight you have, Chris ------------------------------------------------------------------------------ Return on Information: Google Enterprise Search pays you back Get the facts. <a href="http://p.sf.net/sfu/google-dev2dev" target="_blank">http://p.sf.net/sfu/google-dev2dev</a> _______________________________________________ Nagios-users mailing list <a href="mailto:Nagios-users@lists.sourceforge.net">Nagios-users@lists.sourceforge.net</a> <a href="https://lists.sourceforge.net/lists/listinfo/nagios-users" target="_blank">https://lists.sourceforge.net/lists/listinfo/nagios-users</a> ::: Please include Nagios version, plugin version (-v) and OS when reporting any issue. ::: Messages without supporting info will risk being sent to /dev/null </blockquote></div>