As part of our current set up we run some external service
checks against remote hosts we monitor (things like check_tcp, ping, check_ssh)
these are currently all active checks but I wondered if you can set check_mk to
write these checks or is it best to manually create them in /etc/objects/services.cfg
and just use the host name you define in main.mk?
As they check network connectivity we prefer to run them
from the nagios server and not run them from the remote host itself
As part of our current set up we run some external service checks against remote hosts we monitor (things like check_tcp, ping, check_ssh) these are currently all active checks but I wondered if you can set check_mk to write these checks or is it best to manually create them in <nagios root>/etc/objects/services.cfg and just use the host name you define in main.mk?
As long as you have no Performance-Problems with running all those
tests locally on the Nagios-Server, the preferred way to do is:
* Setup those network checks as usual as active Checks in Nagios
* Use check_mk just to create entries for the hosts
Certain Check_mk features will not work in that case, for
example service aggregation and cluster checks.
If that is not OK for you or if you have performance problems, you
could consider running the checks locally on the hosts via MRPE.
I know, that this is not *quite* the same, as running the from
another host, but the circumstances where:
+ a service can be reached from localhost
+ the host can be reached from the network
+ the service can *not* be reached from the network
are rare and mostly to misconfiguration at initial setup.
The advantages of running the checks locally on the hosts
are:
* Nagios will scale better since it does not have to do
several more active checks per host.
* Check_MK can inventorize those checks
* Check_MK will create your Nagios configuration
* You can use clustering and service aggregation
* You can use check_mk for defining service groups and
service dependiencies.
Greetings,
Mathias
···
--
__ __ _ __
Mathias Kettner | \/ | |/ / M A T H I A S K E T T N E R
Preysingstr. 74 | |\/| | ' /
81667 M�nchen | | | | . \ Linux Beratung & Schulung
089 / 444 09 662 |_| |_|_|\_\ http://mathias-kettner.de
Thanks for this, I guess the best way would be to set up the 2 different
options and test it out. Then I can kick it back to the system architects
and let them decide which one to use (I love being able to delegate upwards
;-))
Cheers
Mike
···
-----Original Message-----
From: Mathias Kettner [mailto:mk@mathias-kettner.de]
Sent: 25 October 2009 16:42
To: Michael Hobbs
Cc: checkmk-en@lists.mathias-kettner.de
Subject: Re: [Check_mk (english)] running active checks alongside check_mk
Hi Michael
As part of our current set up we run some external service checks
against remote hosts we monitor (things like check_tcp, ping, check_ssh)
these are currently all active checks but I wondered if you can set
check_mk to write these checks or is it best to manually create them in
<nagios root>/etc/objects/services.cfg and just use the host name you
define in main.mk?
As long as you have no Performance-Problems with running all those
tests locally on the Nagios-Server, the preferred way to do is:
* Setup those network checks as usual as active Checks in Nagios
* Use check_mk just to create entries for the hosts
Certain Check_mk features will not work in that case, for
example service aggregation and cluster checks.
If that is not OK for you or if you have performance problems, you
could consider running the checks locally on the hosts via MRPE.
I know, that this is not *quite* the same, as running the from
another host, but the circumstances where:
+ a service can be reached from localhost
+ the host can be reached from the network
+ the service can *not* be reached from the network
are rare and mostly to misconfiguration at initial setup.
The advantages of running the checks locally on the hosts
are:
* Nagios will scale better since it does not have to do
several more active checks per host.
* Check_MK can inventorize those checks
* Check_MK will create your Nagios configuration
* You can use clustering and service aggregation
* You can use check_mk for defining service groups and
service dependiencies.
Greetings,
Mathias
--
__ __ _ __
Mathias Kettner | \/ | |/ / M A T H I A S K E T T N E R
Preysingstr. 74 | |\/| | ' /
81667 München | | | | . \ Linux Beratung & Schulung
089 / 444 09 662 |_| |_|_|\_\ http://mathias-kettner.de
I was reading your interview with Ethan and was interested in your comments
<snip>
MK: The largest installation currently performs 17,500 checks per minute,
and is soon going to be expanded by several hundred Windows servers.
The load on the 4 CPU machine is currently at 6 - whereas the majority of
CPU time consists of IO wait (Linux includes processes waiting for disk IO
in the load calculation). RRD-data is written at a rate of about 5 MB per
second. When deploying the RRD cache, I assume 30,000 to 40,000 checks per
minute to be achievable
</snip>
I was wondering if you could give out a few more details on this set up?
e.g. number and type of hosts monitored
rough number of service checks per hosts and the type of checks done
the reason I ask is we have a lot or people in our company who look at
Nagios and the first thing they ask is how scalable is it, so having some
data like this would be invaluable to me to get them to shut up and take
Nagios and check_mk as a viable option for monitoring
I'm sorry that I do not have precise numbers. Currently
there are ~ 21.000 Checks, most of them done via Check_MK.
There are about 800 hosts, 250 of them Linux/Unix host with
up to 200 checks for the more complex ones.
Mathias
···
I was wondering if you could give out a few more details on this set up?
e.g. number and type of hosts monitored
rough number of service checks per hosts and the type of checks done
the reason I ask is we have a lot or people in our company who look at
Nagios and the first thing they ask is how scalable is it, so having some
data like this would be invaluable to me to get them to shut up and take
Nagios and check_mk as a viable option for monitoring
cheers
Mike
--
__ __ _ __
Mathias Kettner | \/ | |/ / M A T H I A S K E T T N E R
Preysingstr. 74 | |\/| | ' /
81667 M�nchen | | | | . \ Linux Beratung & Schulung
089 / 444 09 662 |_| |_|_|\_\ http://mathias-kettner.de
