Passive checks greatly delaying active checks

[Andreas Ericsson]

Ludwig Pummer wrote:
> Hello folks,
> 
> I'm experimenting with a distributed monitoring + failover configuration
> between 2 nagios servers, each actively monitoring its own group of
> hosts unless the other nagios server fails.
> 
> Nagios server #1 is a dual Xeon 2.4GHz (hyperthreading off) w/ 1.5GB RAM
> running RHES 3. Nagios server #2 is a dual Xeon 3.2GHz (hyperthreading
> on) w/ 3.0GB RAM running RHES 3 in 64-bit mode.
> 
> Both are running Nagios 1.2. They are running idential Nagios
> configurautions with the exception of active/passive services. My nagios
> init script sends DISABLE_HOST_SVC_CHECKS,
> DISABLE_HOST_SVC_NOTIFICATIONS, and DISABLE_HOST_NOTIFICATIONS commands
> at nagios startup for those hosts which that particular nagios server is
> not supposed to actively monitor. I've got 472 hosts and 1487 services
> total. Server #1 has 686 active and 801 passive service checks. Server
> #2 has 805 active and 682 passive service checks. Both machines have an
> ocsp_command set up which will send_nsca to the other nagios server the
> results of any active checks.
> 
> The issue I'm having is that when I have nsca running to receive passive
> checks from the other host, active checks are delayed a lot (from under
> 30 seconds without nsca to 15-25 minutes with nsca running). My
> command_check_interval is set to -1. I have log_passive_service_checks
> set to 1 for testing, so I can see the nsca results coming in. I don't
> see why receiving passive checks is causing such large delays in my
> active checks.
> 

It's because the FIFO becomes a bottleneck if you're doing more than 
just a few passive service checks. Try lowering the 
(something)_reaper_frequency in nagios.cfg. It might fix it, or at least 
help up the situation a bit.

-- 
Andreas Ericsson                   andreas.ericsson at op5.se
OP5 AB                             www.op5.se
Lead Developer


-------------------------------------------------------
This SF.Net email is sponsored by:
Power Architecture Resource Center: Free content, downloads, discussions,
and more. http://solutions.newsforge.com/ibmarch.tmpl
_______________________________________________
Nagios-users mailing list
Nagios-users at lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/nagios-users
::: Please include Nagios version, plugin version (-v) and OS when reporting any issue. 
::: Messages without supporting info will risk being sent to /dev/null