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Features
Icinga
Figure 3: A manual check of commands in commands.cfg reveals the culprit.
Figure 4: Mail dispatched by Icinga is short and to the point.
need to consider the interval between
checks. One useful feature is the ability
to define time slots, within which
Icinga will perform checks and, if
necessary, notify the administrator.
Here, time limitations or holidays can
be defined.
The contact configuration can include
email addresses or cell phone numbers,
but to integrate each contact
with, for example, an Email2SMS
gateway or a Text2Speech system
(e.g., Festival), you need a matching
command.
Icinga can use macros, which noticeably
simplifies and accelerates many
tasks because you can use a single
command for multiple hosts and services.
Listings 2 and 3 give examples
of macros.
All services defined for monitoring
the file server include a check_nrpe
instruction with an exclamation
mark. Each exclamation mark can
be followed by an argument, which
in turn is evaluated by the macros in
other definitions. Macros are nested
in $ signs.
After creating the configuration files
and storing them in etc/objects, you
still need to tell Icinga by adding a
new
Icinga with /etc/init.d/icinga restart.
GUI and Messages
Icinga works without a graphical
interface, but it’s much nicer to have
one. The standard interface can’t
deny its Nagios ancestry, but it is
clear-cut and intuitive.
If everything is working, you’ll see a
lot of green in the user interface (Figure
1), but if something goes wrong
somewhere, the color will change and
move closer and closer to red to reflect
the status of the hosts or services
(Figures 2 and 3). Status messages
are typically linked, so that clicking
one takes you to more detailed information.
If something is so drastically wrong
that a message is necessary, Icinga
will check its complex ruleset to see
whether it should send a message
and, if so, to whom (Figure 4). The
filters through which the message
passes check the following: whether
notifications are required, if the
problem occurred at a time when the
host and service should be running,
if messages should be sent for this
service in the current time slot, and
what the contacts linked to the service
actually want. Each contact can
cfg_file=/usr/local/icinga/etc/objects/
object.cfg
to the main configuration file, /etc/
icinga.cfg. After doing so, you
should verify the configuration,
/path‐to‐Icinga/bin/icinga ‐v
/path‐to‐Icinga/etc/icinga.cfg;
assuming there are no errors, restart
Figure 5: Icinga Web beta was not entirely convincing. Version 1.0.3 is out now.
18 Admin 01 www.admin-magazine.com