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Icinga 2 Features


Icinga 2 supports three different types of logging:

  • File logging
  • Syslog (on Linux/UNIX)
  • Console logging (STDOUT on tty)

You can enable additional loggers using the icinga2 feature enable and icinga2 feature disable commands to configure loggers:

Feature Description
debuglog Debug log (path: /var/log/icinga2/debug.log, severity: debug or higher)
mainlog Main log (path: /var/log/icinga2/icinga2.log, severity: information or higher)
syslog Syslog (severity: warning or higher)

By default file the mainlog feature is enabled. When running Icinga 2 on a terminal log messages with severity information or higher are written to the console.

Log Rotation

Packages provide a configuration file for logrotate on Linux/Unix. Typically this is installed into /etc/logrotate.d/icinga2 and modifications won’t be overridden on upgrade.

Instead of sending the reload HUP signal, logrotate sends the USR1 signal to notify the Icinga daemon that it has rotate the log file. Icinga reopens the log files then:

  • /var/log/icinga2/icinga2.log (requires mainlog enabled)
  • /var/log/icinga2/debug.log (requires debuglog enabled)
  • /var/log/icinga2/erorr.log

By default, log files will be rotated daily.

Core Backends


The REST API is documented here as a core feature.

IDO Database (DB IDO)

The IDO (Icinga Data Output) feature for Icinga 2 takes care of exporting all configuration and status information into a database. The IDO database is used by Icinga Web 2 as data backend.

Details on the installation can be found in the Configuring DB IDO chapter. Details on the configuration can be found in the IdoMysqlConnection and IdoPgsqlConnection object configuration documentation.

DB IDO Health

If the monitoring health indicator is critical in Icinga Web 2, you can use the following queries to manually check whether Icinga 2 is actually updating the IDO database.

Icinga 2 writes its current status to the icinga_programstatus table every 10 seconds. The query below checks 60 seconds into the past which is a reasonable amount of time – adjust it for your requirements. If the condition is not met, the query returns an empty result.


Use check plugins to monitor the backend.

Replace the default string with your instance name if different.

Example for MySQL:

# mysql -u root -p icinga -e "SELECT status_update_time FROM icinga_programstatus ps
  JOIN icinga_instances i ON ps.instance_id=i.instance_id
  WHERE (UNIX_TIMESTAMP(ps.status_update_time) > UNIX_TIMESTAMP(NOW())-60)
  AND i.instance_name='default';"

| status_update_time  |
| 2014-05-29 14:29:56 |

Example for PostgreSQL:

# export PGPASSWORD=icinga; psql -U icinga -d icinga -c "SELECT ps.status_update_time FROM icinga_programstatus AS ps
  JOIN icinga_instances AS i ON ps.instance_id=i.instance_id
  WHERE ((SELECT extract(epoch from status_update_time) FROM icinga_programstatus) > (SELECT extract(epoch from now())-60))
  AND i.instance_name='default'";

 2014-05-29 15:11:38+02
(1 Zeile)

A detailed list on the available table attributes can be found in the DB IDO Schema documentation.

DB IDO in Cluster HA Zones

The DB IDO feature supports High Availability in the Icinga 2 cluster.

By default, both endpoints in a zone calculate the endpoint which activates the feature, the other endpoint automatically pauses it. If the cluster connection breaks at some point, the paused IDO feature automatically does a failover.

You can disable this behaviour by setting enable_ha = false in both feature configuration files.

DB IDO Cleanup

Objects get deactivated when they are deleted from the configuration. This is visible with the is_active column in the icinga_objects table. Therefore all queries need to join this table and add WHERE is_active=1 as condition. Deleted objects preserve their history table entries for later SLA reporting.

Historical data isn’t purged by default. You can enable the least kept data age inside the cleanup configuration attribute for the IDO features IdoMysqlConnection and IdoPgsqlConnection.

Example if you prefer to keep notification history for 30 days:

  cleanup = {
     notifications_age = 30d
     contactnotifications_age = 30d

The historical tables are populated depending on the data categories specified. Some tables are empty by default.

DB IDO Tuning

As with any application database, there are ways to optimize and tune the database performance.

General tips for performance tuning:

Re-creation of indexes, changed column values, etc. will increase the database size. Ensure to add health checks for this, and monitor the trend in your Grafana dashboards.

In order to optimize the tables, there are different approaches. Always keep in mind to have a current backup and schedule maintenance downtime for these kind of tasks!


mariadb> OPTIMIZE TABLE icinga_statehistory;


Tables might not support optimization at runtime. This can take a long time.

Table does not support optimize, doing recreate + analyze instead.

If you want to optimize all tables in a specified database, there is a script called mysqlcheck. This also allows to repair broken tables in the case of emergency.

mysqlcheck --optimize icinga


icinga=# vacuum;


Don’t use VACUUM FULL as this has a severe impact on performance.


Whenever a host or service check is executed, or received via the REST API, best practice is to provide performance data.

This data is parsed by features sending metrics to time series databases (TSDB):

Metrics, state changes and notifications can be managed with the following integrations:

Graphite Writer

Graphite is a tool stack for storing metrics and needs to be running prior to enabling the graphite feature.

Icinga 2 writes parsed metrics directly to Graphite’s Carbon Cache TCP port, defaulting to 2003.

You can enable the feature using

# icinga2 feature enable graphite

By default the GraphiteWriter feature expects the Graphite Carbon Cache to listen at on TCP port 2003.

Graphite Schema

The current naming schema is defined as follows. The Icinga Web 2 Graphite module depends on this schema.

The default prefix for hosts and services is configured using runtime macroslike this:


You can customize the prefix name by using the host_name_template and service_name_template configuration attributes.

The additional levels will allow fine granular filters and also template capabilities, e.g. by using the check command disk for specific graph templates in web applications rendering the Graphite data.

The following characters are escaped in prefix labels:

Character Escaped character
whitespace _
. _
\ _
/ _

Metric values are stored like this:


The following characters are escaped in performance labels parsed from plugin output:

Character Escaped character
whitespace _
\ _
/ _
:: .

Note that labels may contain dots (.) allowing to add more subsequent levels inside the Graphite tree. :: adds support for multi performance labels and is therefore replaced by ..

By enabling enable_send_thresholds Icinga 2 automatically adds the following threshold metrics:


By enabling enable_send_metadata Icinga 2 automatically adds the following metadata metrics:


Metadata metric overview:

metric description
current_attempt current check attempt
max_check_attempts maximum check attempts until the hard state is reached
reachable checked object is reachable
downtime_depth number of downtimes this object is in
acknowledgement whether the object is acknowledged or not
execution_time check execution time
latency check latency
state current state of the checked object
state_type 0=SOFT, 1=HARD state

The following example illustrates how to configure the storage schemas for Graphite Carbon Cache.

# intervals like PNP4Nagios uses them per default
pattern = ^icinga2\.
retentions = 1m:2d,5m:10d,30m:90d,360m:4y

InfluxDB Writer

Once there are new metrics available, Icinga 2 will directly write them to the defined InfluxDB HTTP API.

You can enable the feature using

# icinga2 feature enable influxdb

By default the InfluxdbWriter feature expects the InfluxDB daemon to listen at on port 8086.

Measurement names and tags are fully configurable by the end user. The InfluxdbWriter object will automatically add a metric tag to each data point. This correlates to the perfdata label. Fields (value, warn, crit, min, max, unit) are created from data if available and the configuration allows it. If a value associated with a tag is not able to be resolved, it will be dropped and not sent to the target host.

Backslashes are allowed in tag keys, tag values and field keys, however they are also escape characters when followed by a space or comma, but cannot be escaped themselves. As a result all trailling slashes in these fields are replaced with an underscore. This predominantly affects Windows paths e.g. C:\ becomes C:_.

The database is assumed to exist so this object will make no attempt to create it currently.

If SELinux is enabled, it will not allow access for Icinga 2 to InfluxDB until the boolean icinga2_can_connect_all is set to true as InfluxDB is not providing its own policy.

More configuration details can be found here.

Instance Tagging

Consider the following service check:

apply Service "disk" for (disk => attributes in host.vars.disks) {
  import "generic-service"
  check_command = "disk"
  display_name = "Disk " + disk
  vars.disk_partitions = disk
  assign where host.vars.disks

This is a typical pattern for checking individual disks, NICs, SSL certificates etc associated with a host. What would be useful is to have the data points tagged with the specific instance for that check. This would allow you to query time series data for a check on a host and for a specific instance e.g. /dev/sda. To do this quite simply add the instance to the service variables:

apply Service "disk" for (disk => attributes in host.vars.disks) {
  vars.instance = disk

Then modify your writer configuration to add this tag to your data points if the instance variable is associated with the service:

object InfluxdbWriter "influxdb" {
  service_template = {
    measurement = "$service.check_command$"
    tags = {
      hostname = "$$"
      service = "$$"
      instance = "$service.vars.instance$"

Elastic Stack Integration

Icingabeat is an Elastic Beat that fetches data from the Icinga 2 API and sends it either directly to Elasticsearch or Logstash.

More integrations:

Elasticsearch Writer

This feature forwards check results, state changes and notification events to an Elasticsearch installation over its HTTP API.

The check results include parsed performance data metrics if enabled.


Elasticsearch 5.x or 6.x are required. This feature has been successfully tested with Elasticsearch 5.6.7 and 6.3.1.

Enable the feature and restart Icinga 2.

# icinga2 feature enable elasticsearch

The default configuration expects an Elasticsearch instance running on localhost on port 9200 and writes to an index calledicinga2`.

More configuration details can be found here.

Current Elasticsearch Schema

The following event types are written to Elasticsearch:

  • icinga2.event.checkresult
  • icinga2.event.statechange
  • icinga2.event.notification

Performance data metrics must be explicitly enabled with the enable_send_perfdata attribute.

Metric values are stored like this:


The following characters are escaped in perfdata labels:

Character Escaped character
whitespace _
\ _
/ _
:: .

Note that perfdata labels may contain dots (.) allowing to add more subsequent levels inside the tree. :: adds support for multi performance labels and is therefore replaced by ..

Icinga 2 automatically adds the following threshold metrics if existing:


Graylog Integration

GELF Writer

The Graylog Extended Log Format (short: GELF) can be used to send application logs directly to a TCP socket.

While it has been specified by the Graylog project as their input resource standard, other tools such as Logstash also support GELF as input type.

You can enable the feature using

# icinga2 feature enable gelf

By default the GelfWriter object expects the GELF receiver to listen at on TCP port 12201. The default source attribute is set to icinga2. You can customize that for your needs if required.

Currently these events are processed: * Check results * State changes * Notifications

OpenTSDB Writer

While there are some OpenTSDB collector scripts and daemons like tcollector available for Icinga 1.x it’s more reasonable to directly process the check and plugin performance in memory in Icinga 2. Once there are new metrics available, Icinga 2 will directly write them to the defined TSDB TCP socket.

You can enable the feature using

# icinga2 feature enable opentsdb

By default the OpenTsdbWriter object expects the TSD to listen at on port 4242.

The current naming schema is<metricname>

for host and service checks. The tag host is always applied.

To make sure Icinga 2 writes a valid metric into OpenTSDB some characters are replaced with _ in the target name:

\  (and space)

The resulting name in OpenTSDB might look like:

www-01 / http-cert / response time

In addition to the performance data retrieved from the check plugin, Icinga 2 sends internal check statistic data to OpenTSDB:

metric description
current_attempt current check attempt
max_check_attempts maximum check attempts until the hard state is reached
reachable checked object is reachable
downtime_depth number of downtimes this object is in
acknowledgement whether the object is acknowledged or not
execution_time check execution time
latency check latency
state current state of the checked object
state_type 0=SOFT, 1=HARD state

While reachable, state and state_type are metrics for the host or service the other metrics follow the current naming schema


with the following tags

tag description
type the check type, one of [host, service]
host hostname, the check ran on
service the service name (if type=service)


You might want to set the tsd.core.auto_create_metrics setting to true in your opentsdb.conf configuration file.

Writing Performance Data Files

PNP and Graphios use performance data collector daemons to fetch the current performance files for their backend updates.

Therefore the Icinga 2 PerfdataWriter feature allows you to define the output template format for host and services helped with Icinga 2 runtime vars.

host_format_template = "DATATYPE::HOSTPERFDATA\tTIMET::$icinga.timet$\tHOSTNAME::$$\tHOSTPERFDATA::$host.perfdata$\tHOSTCHECKCOMMAND::$host.check_command$\tHOSTSTATE::$host.state$\tHOSTSTATETYPE::$host.state_type$"
service_format_template = "DATATYPE::SERVICEPERFDATA\tTIMET::$icinga.timet$\tHOSTNAME::$$\tSERVICEDESC::$$\tSERVICEPERFDATA::$service.perfdata$\tSERVICECHECKCOMMAND::$service.check_command$\tHOSTSTATE::$host.state$\tHOSTSTATETYPE::$host.state_type$\tSERVICESTATE::$service.state$\tSERVICESTATETYPE::$service.state_type$"

The default templates are already provided with the Icinga 2 feature configuration which can be enabled using

# icinga2 feature enable perfdata

By default all performance data files are rotated in a 15 seconds interval into the /var/spool/icinga2/perfdata/ directory as host-perfdata.<timestamp> and service-perfdata.<timestamp>. External collectors need to parse the rotated performance data files and then remove the processed files.


The MK Livestatus project implements a query protocol that lets users query their Icinga instance for status information. It can also be used to send commands.

The Livestatus component that is distributed as part of Icinga 2 is a re-implementation of the Livestatus protocol which is compatible with MK Livestatus.


Only install the Livestatus feature if your web interface or addon requires you to do so. Icinga Web 2 does not need Livestatus.

Details on the available tables and attributes with Icinga 2 can be found in the Livestatus Schema section.

You can enable Livestatus using icinga2 feature enable:

# icinga2 feature enable livestatus

After that you will have to restart Icinga 2:

# systemctl restart icinga2

By default the Livestatus socket is available in /var/run/icinga2/cmd/livestatus.

In order for queries and commands to work you will need to add your query user (e.g. your web server) to the icingacmd group:

# usermod -a -G icingacmd www-data

The Debian packages use nagios as the user and group name. Make sure to change icingacmd to nagios if you’re using Debian.

Change www-data to the user you’re using to run queries.

In order to use the historical tables provided by the livestatus feature (for example, the log table) you need to have the CompatLogger feature enabled. By default these logs are expected to be in /var/log/icinga2/compat. A different path can be set using the compat_log_path configuration attribute.

# icinga2 feature enable compatlog

Livestatus Sockets

Other to the Icinga 1.x Addon, Icinga 2 supports two socket types

  • Unix socket (default)
  • TCP socket

Details on the configuration can be found in the LivestatusListener object configuration.

Livestatus GET Queries


All Livestatus queries require an additional empty line as query end identifier. The nc tool (netcat) provides the -U parameter to communicate using a unix socket.

There also is a Perl module available in CPAN for accessing the Livestatus socket programmatically: Monitoring::Livestatus

Example using the unix socket:

# echo -e "GET services\n" | /usr/bin/nc -U /var/run/icinga2/cmd/livestatus

Example using the tcp socket listening on port `6558`:

# echo -e 'GET services\n' | netcat 6558

# cat servicegroups <<EOF
GET servicegroups


(cat servicegroups; sleep 1) | netcat 6558

Livestatus COMMAND Queries

A list of available external commands and their parameters can be found here

$ echo -e 'COMMAND <externalcommandstring>' | netcat 6558

Livestatus Filters

and, or, negate

Operator Negate Description
= != Equality
~ !~ Regex match
=~ !=~ Equality ignoring case
~~ !~~ Regex ignoring case
< Less than
> Greater than
<= Less than or equal
>= Greater than or equal

Livestatus Stats

Schema: “Stats: aggregatefunction aggregateattribute”

Aggregate Function Description
avg sum / count
std standard deviation
suminv sum (1 / value)
avginv suminv / count
count ordinary default for any stats query if not aggregate function defined


GET hosts
Filter: has_been_checked = 1
Filter: check_type = 0
Stats: sum execution_time
Stats: sum latency
Stats: sum percent_state_change
Stats: min execution_time
Stats: min latency
Stats: min percent_state_change
Stats: max execution_time
Stats: max latency
Stats: max percent_state_change
OutputFormat: json
ResponseHeader: fixed16

Livestatus Output

  • CSV

CSV output uses two levels of array separators: The members array separator is a comma (1st level) while extra info and host|service relation separator is a pipe (2nd level).

Separators can be set using ASCII codes like:

Separators: 10 59 44 124
  • JSON

Default separators.

Livestatus Error Codes

Code Description
200 OK
404 Table does not exist
452 Exception on query

Livestatus Tables

Table Join Description
hosts   host config and status attributes, services counter
hostgroups   hostgroup config, status attributes and host/service counters
services hosts service config and status attributes
servicegroups   servicegroup config, status attributes and service counters
contacts   contact config and status attributes
contactgroups   contact config, members
commands   command name and line
status   programstatus, config and stats
comments services status attributes
downtimes services status attributes
timeperiods   name and is inside flag
endpoints   config and status attributes
log services, hosts, contacts, commands parses compatlog and shows log attributes
statehist hosts, services parses compatlog and aggregates state change attributes
hostsbygroup hostgroups host attributes grouped by hostgroup and its attributes
servicesbygroup servicegroups service attributes grouped by servicegroup and its attributes
servicesbyhostgroup hostgroups service attributes grouped by hostgroup and its attributes

The commands table is populated with CheckCommand, EventCommand and NotificationCommand objects.

A detailed list on the available table attributes can be found in the Livestatus Schema documentation.

Deprecated Features

Status Data Files


This feature is DEPRECATED and will be removed in Icinga 2 v2.11.

Icinga 1.x writes object configuration data and status data in a cyclic interval to its objects.cache and status.dat files. Icinga 2 provides the StatusDataWriter object which dumps all configuration objects and status updates in a regular interval.

# icinga2 feature enable statusdata

If you are not using any web interface or addon which uses these files, you can safely disable this feature.

Compat Log Files


This feature is DEPRECATED and will be removed in Icinga 2 v2.11.

The Icinga 1.x log format is considered being the Compat Log in Icinga 2 provided with the CompatLogger object.

These logs are used for informational representation in external web interfaces parsing the logs, but also to generate SLA reports and trends. The Livestatus feature uses these logs for answering queries to historical tables.

The CompatLogger object can be enabled with

# icinga2 feature enable compatlog

By default, the Icinga 1.x log file called icinga.log is located in /var/log/icinga2/compat. Rotated log files are moved into var/log/icinga2/compat/archives.

External Command Pipe


Please use the REST API as modern and secure alternative for external actions.


This feature is DEPRECATED with 2.11 and will be removed in future releases. Check the roadmap.

Icinga 2 provides an external command pipe for processing commands triggering specific actions (for example rescheduling a service check through the web interface).

In order to enable the ExternalCommandListener configuration use the following command and restart Icinga 2 afterwards:

# icinga2 feature enable command

Icinga 2 creates the command pipe file as /var/run/icinga2/cmd/icinga2.cmd using the default configuration.

Web interfaces and other Icinga addons are able to send commands to Icinga 2 through the external command pipe, for example for rescheduling a forced service check:

# /bin/echo "[`date +%s`] SCHEDULE_FORCED_SVC_CHECK;localhost;ping4;`date +%s`" >> /var/run/icinga2/cmd/icinga2.cmd

# tail -f /var/log/messages

Oct 17 15:01:25 icinga-server icinga2: Executing external command: [1382014885] SCHEDULE_FORCED_SVC_CHECK;localhost;ping4;1382014885
Oct 17 15:01:25 icinga-server icinga2: Rescheduling next check for service 'ping4'

A list of currently supported external commands can be found here.

Detailed information on the commands and their required parameters can be found on the Icinga 1.x documentation.

Check Result Files


This feature is DEPRECATED and will be removed in Icinga 2 v2.11.

Icinga 1.x writes its check result files to a temporary spool directory where they are processed in a regular interval. While this is extremely inefficient in performance regards it has been rendered useful for passing passive check results directly into Icinga 1.x skipping the external command pipe.

Several clustered/distributed environments and check-aggregation addons use that method. In order to support step-by-step migration of these environments, Icinga 2 supports the CheckResultReader object.

There is no feature configuration available, but it must be defined on-demand in your Icinga 2 objects configuration.

object CheckResultReader "reader" {
  spool_dir = "/data/check-results"