Service dependencies

[Tobias Mucke]

Hi,

since we are using Nagios in a large environment here, we also have to fight with service dependencies and the approach how to configure it. What I would like to see in Nagios is the possibility to define that a service always depends on another service without even mentioning a host or hostgroup. Look at the example.

I have a service called disk_os which checks all filesystems of a system or even a large group of systems. I do this by using nrpe. To check if nrpe is running I have a service called nrpe. Today I have to configure for every host with  disk_os a single servicedependency to nrpe.

What I want to do is, to define that disk_os will always depend on nrpe, so I don't have to mention that for each host again and again.

Thanks.

Tobias


-----Original Message-----
From: "Thomas Guyot-Sionnest" <Thomas at zango.com>
To: "Thomas Sluyter" <nagios at kilala.nl>,"Nagios-Devel" <nagios-devel at lists.sourceforge.net>
Date: Wed, 18 Oct 2006 23:51:25 -0700
Subject: Re: [Nagios-devel] Service dependencies

> 
> Sorry to bring up an old thread, but there were no follow up on this. I
> just find myself in the same situation (need one-to one mapping for
> every hosts) and remembered this old thread.
> 
> How hard would if be to add a flag in servicedependency definitions that
> force every service dependency to reside on the same host, and ignore
> missing services.
> 
> So I could write something like this:
> 
> define servicedependency {
>   hostgroup_name                pool1,pool2
>   service_description           Master service
>   dependent_hostgroup_name      pool1,pool2
>   dependent_service_description Slave 1,Slave 2,Slave 3
>   same_host_dependency          1
>   notification_failure_criteria c,u
> }
> 
> And I'd get:
> 1: dependencies across services on the same host for every hosts defined
> in pool1 and pool2
> 2: missing dependent services would be silently dropped.
> 
> Or to be more flexible different values for same_host_dependency could
> determine if Nagios does #1 or #1 & #2.
> 
> If you don't like #2, doing #1 would already reduce significantly the
> config required.
> 
> I never checked the pre-flight code, but I'd assume it shouldn't be that
> hard. I guess all you have to do is skip dependency creation on
> conditional statements.
> 
> Thanks,
> 
> Thomas
> 
> > -----Original Message-----
> > From: nagios-devel-bounces at lists.sourceforge.net [mailto:nagios-devel-
> > bounces at lists.sourceforge.net] On Behalf Of Thomas Sluyter
> > Sent: Monday, June 12, 2006 5:58
> > To: Nagios-Devel
> > Subject: Re: [Nagios-devel] Service dependencies
> > 
> > I'm sorry if this is the second time this message gets sent to the
> > list. I had a hunch that it didn't make it the first time I sent it...
> > 
> > ============
> > 
> > Hi all.
> > 
> > I was actually wondering about the exact same thing Dirk was thinking
> > about! Such a shortcut would really help out in easing the use of
> > dependencies.
> > 
> > > Try this...
> > >
> > > define servicedependency{
> > > hostgroup_name windows-servers
> > > service_description NRPE_NT
> > > dependent_hostgroup_name windows-servers
> > > dependent_service_description Drive_C
> > > }
> > 
> > Ethan's solution wouldn't work if you look at it logically. Why?
> > Because you're telling Nagios that:
> > * All instances of service A in hostgroup X
> > * Depend on all instances of service B in hostgroup X.
> > 
> > Meaning that all instances of A will "fail" if -any- instance of B
> > goes down. That's not what we want to happen, is it? :p
> > 
> > Or am I completely off on this? Might be that I'm not reading this
> > correctly.
> > 
> > As Dirk said: it would be great if there was some shortcut for
> > telling Nagios that you want all instances of service A in hostgroup
> > X to be dependant of service B on -their-own- host. That way you
> > could take care of all dependencies for a whole hostgroup in a matter
> > of a few dozen lines of code.
> > 
> > 
> > - Thomas Sluyter (Cailin)
> > 
> > -----------------------
> > This thread is located in the archive at this URL:
> > http://www.nagiosexchange.org/nagios-devel.33.0.html?
> > &tx_maillisttofaq_pi1[showUid]=18830
> > 
> > 
> > 
> > _______________________________________________
> > Nagios-devel mailing list
> > Nagios-devel at lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/nagios-devel
> 
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Using Tomcat but need to do more? Need to support web services, security?
Get stuff done quickly with pre-integrated technology to make your job easier
Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642