Child pages
  • hidden/unvisible hostgroups or service-sets - how to use
Skip to end of metadata
Go to start of metadata

The "hidden hostgroup" easter egg implemented in Nagios 4 means you can

use hostgroups which have "register 0" to assign services to. It was

originally an idea by Christian Anton actually (waaaay back, afair),

but got implemented by accident during the Nagios 4.0 config revamp

as a sideeffect of the optimizations.

Basically, it means that you can create a config like this;


define hostgroup {

  hostgroup_name      _sset_pop3server

  # register 0 means this never shows up in the UI

  register            0



define service {

  use                 some-random-service-template

  check_command  check_pop3!$host:_SSETPOP3WARN$!$host:_SSETPOP3CRIT$

  service_description POP3 service



define host {

  use some-random-host-template

  host_name pop3server

  hostgroups _sset_pop3server






and things will just work.


Note that in order to get any kind of performance out of using this

on a larger-than-pretty-small scale, it's necessary to implement some

caching in Nagios so most command macros are only resolved once instead

of every time. There's a plan for that, and it can be implemented

pretty quickly.


The (very loose) idea is to add some sort of support for this in

Nacoma. Possibly by converting existing "host profiles" or by using

the already-coined term "service sets" and build basic monitoring

for particular types of equipment (such as ms-nsclient, unix-nrpe,

server-snmp, vmware-guest etc, etc).


The long-term idea is still to implement "callable" service sets,

where one can do things like



define host {

  host_name MS Exchange 1

  service_set msexchange(warn=10,crit=20,sendqwarn=1000)



define serviceset {

  serviceset_name mail-server

  define service {

    service_description POP3 service

    check_command  check_pop3!%{warn}!%{crit}


  define service {

    service_description SMTP service

    check_command $PLUGIN_DIR$/check_smtp!%{warn}!%{crit}




define serviceset {

  serviceset_name ms-exchange

  includes mail-server

  define service {

    service_description MSExchange SendQ

    check_command $PLUGIN_DIR$/check_nsclient!%{sendqwarn}






although it's possible we'll make a special prefix (sset_) for

hosts to allow them to pass variables to service-sets as well.


If you want to make servicesets right now, please utilize the

_sset prefix for custom variables for hosts. Use the same prefix

for hostgroup_names, and use _service_set "somename" for services

you want included in the set. That will allow us to automagically

manage servicesets.


The ui honey on top of the Nagios syntax voodoo will most likely

be delivered in 6.2 in some form or other, even if it appears as

a fairly simple hack.

1 Comment

  1. Unknown User (canton)

    unfortunately, this seems not to be possible with Nacoma. Would it be worth a Feature Request?