icinga2/doc/7-troubleshooting.md

# <a id="troubleshooting"></a> Icinga 2 Troubleshooting

For a more verbose output of the Icinga 2 daemon increase the
`severity` attribute of the [logs](#logging) to `notice` or
`debug`.

## <a id="troubleshooting-information-required"></a> Which information is required

* Which distribution and version
* How was Icinga 2 installed (and which repository in case)
* Run `icinga2 --version`
* Provide complete configuration snippets explaining your problem in detail
* Provide complete logs targetting your problem
* If the check command failed - what's the output of your manual plugin tests?
* In case of [debugging](#debug) Icinga 2, the full back traces and outputs

## <a id="troubleshooting-enable-debug-output"></a> Enable Debug Output

Run Icinga 2 in the foreground with debugging enabled. Specify the console
log severity as an additional parameter argument to `-x`.

    # /usr/sbin/icinga2 -c /etc/icinga2/icinga2.conf -x notice

Additionally you can enable the debug log using

    # icinga2-enable-feature debuglog
    # service icinga2 restart
    # tail -f /var/log/icinga2/debug.log

## <a id="list-configuration-objects"></a> List Configuration Objects

The `icinga2-list-objects` tool can be used to list all configuration objects and their
attributes. The tool also shows where each of the attributes was modified:

    # icinga2-list-objects
    Object 'apt' of type 'CheckCommand':
      * templates = ['apt', 'plugin-check-command']
        % modified in /usr/share/icinga2/include/command-plugins.conf, lines 458:1-462:1
        % modified in /usr/share/icinga2/include/command.conf, lines 34:1-36:1
      * __name = 'apt'
      * command = ['/usr/lib/nagios/plugins/check_apt']
        % modified in /usr/share/icinga2/include/command-plugins.conf, lines 461:2-461:39
      * methods
        % modified in /usr/share/icinga2/include/command.conf, lines 35:2-35:32
        * execute = 'PluginCheck'
          % modified in /usr/share/icinga2/include/command.conf, lines 35:2-35:32
      * type = 'CheckCommand'
    [...]


## <a id="checks-not-executed"></a> Checks are not executed

* Check the debug log to see if the check command gets executed
* Verify that failed depedencies do not prevent command execution
* Make sure that the plugin is executable by the Icinga 2 user (run a manual test)
* Make sure the [checker](#features) feature is enabled.

Examples:

    # sudo -u icinga /usr/lib/nagios/plugins/check_ping -4 -H 127.0.0.1 -c 5000,100% -w 3000,80%

    # icinga2-enable-feature checker
    The feature 'checker' is already enabled.


## <a id="notifications-not-sent"></a> Notifications are not sent

* Check the debug log to see if a notification is triggered
* If yes, verify that all conditions are satisfied
* Are any errors on the notification command execution logged?

Verify the following configuration

* Is the host/service the `enable_notifications` attribute set, and if, to which value?
* Do the notification attributes `states`, `types`, `period` match the notification conditions?
* Do the user attributes `states`, `types`, `period` match the notification conditions?
* Are there any notification `begin` and `end` times configured?
* Make sure the [notification](#features) feature is enabled.
* Does the referenced NotificationCommand work when executed as Icinga user on the shell?

Examples:

    # icinga2-enable-feature notification
    The feature 'notification' is already enabled.

## <a id="feature-not-working"></a> Feature is not working

* Make sure that the feature configuration is enabled by symlinking from `features-available/`
to `features-enabled` and that the latter is included in [icinga2.conf](#icinga2-conf).
* Are the feature attributes set correctly according to the documentation?
* Any errors on the logs?

## <a id="configuration-ignored"></a> Configuration is ignored

* Make sure that the line(s) are not [commented](#comments) (starting with `//` or `#`, or
encapsulated by `/* ... */`).
* Is the configuration file included in [icinga2.conf](#icinga2-conf)?

## <a id="configuration-attribute-inheritance"></a> Configuration attributes are inherited from

Icinga 2 allows you to import templates using the [import](#import) keyword. If these templates
contain additional attributes, your objects will automatically inherit them. You can override
or modify these attributes in the current object.

## <a id="check-command-definitions"></a> Where are the check command definitions

Icinga 2 ships additional [plugin check command definitions](#plugin-check-commands) which are
included using

    include <itl>
    include <plugins>

in [icinga2.conf](#icinga2-conf). These configurations will be overridden on upgrade, so please
send modifications as proposed patches upstream. The default include path is set to
`LocalStateDir + "/share/icinga2/includes"`.

You should add your own command definitions to a new file in `conf.d/` called `commands.conf`
or similar.


## <a id="troubleshooting-cluster"></a> Cluster Troubleshooting

You should configure the [cluster health checks](#cluster-health-check) if you haven't
done so already.

> **Note**
>
> Some problems just exist due to wrong file permissions or packet filters applied. Make
> sure to check these in the first place.

### <a id="troubleshooting-cluster-connection-errors"></a> Cluster Troubleshooting Connection Errors

General connection errors normally lead you to one of the following problems:

* Wrong network configuration
* Packet loss on the connection
* Firewall rules preventing traffic

Use tools like `netstat`, `tcpdump`, `nmap`, etc to make sure that the cluster communication
happens (default port is `5665`).

    # tcpdump -n port 5665 -i any

    # netstat -tulpen | grep icinga

    # nmap yourclusternode.localdomain

### <a id="troubleshooting-cluster-ssl-errors"></a> Cluster Troubleshooting SSL Errors

If the cluster communication fails with cryptic SSL error messages, make sure to check
the following

* File permissions on the SSL certificate files
* Does the used CA match for all cluster endpoints?

Examples:

    # ls -la /etc/icinga2/pki


### <a id="troubleshooting-cluster-message-errors"></a> Cluster Troubleshooting Message Errors

At some point, when the network connection is broken or gone, the Icinga 2 instances
will be disconnected. If the connection can't be re-established between zones and endpoints,
they remain in a Split-Brain-mode and history may differ.

Although the Icinga 2 cluster protocol stores historical events in a replay log for later synchronisation,
you should make sure to check why the network connection failed.

### <a id="troubleshooting-cluster-config-sync"></a> Cluster Troubleshooting Config Sync

If the cluster zones do not sync their configuration, make sure to check the following:

* Within a config master zone, only one configuration master is allowed to have its config in `/etc/icinga2/zones.d`.
** The master syncs the configuration to `/var/lib/icinga2/api/zones/` during startup and only syncs valid configuration to the other nodes
** The other nodes receive the configuration into `/var/lib/icinga2/api/zones/`
* The `icinga2.log` log file will indicate whether this ApiListener [accepts config](#zone-config-sync-permissions), or not


## <a id="debug"></a> Debug Icinga 2

Make sure that the debug symbols are available for Icinga 2.
The Icinga 2 packages provide a debug package which must be
installed separately for all involved binaries, like `icinga2-bin`
or `icinga2-ido-mysql`.

    # yum install icinga2-debuginfo

    # zypper install icinga2-bin-debuginfo icinga2-ido-mysql-debuginfo

    # apt-get install icinga2-dbg

Compiled binaries require the `-DCMAKE_BUILD_TYPE=RelWithDebInfo` or
`-DCMAKE_BUILD_TYPE=Debug` cmake build flags.

### <a id="development-debug-gdb"></a> GDB

Call GDB with the binary and all arguments and run it in foreground.

    # gdb --args /usr/sbin/icinga2 -c /etc/icinga2/icinga2.conf -x

### <a id="development-debug-gdb-run"></a> GDB Run

Run the application.

    (gdb) r

Kill the running application.

    (gdb) k

Continue after breakpoint.

    (gdb) c

### <a id="development-debug-gdb-backtrace"></a> GDB Backtrace

If Icinga 2 aborted its operation abnormally, generate a backtrace.

    (gdb) bt
    (gdb) bt full

>**Tip**
>
> If you're opening an issue at [https://dev.icinga.org] make sure
> to attach as much detail as possible.


### <a id="development-debug-gdb-backtrace-stepping"></a> GDB Backtrace Stepping

Identifying the problem may require stepping into the backtrace, analysing
the current scope, attributes, and possible unmet requirements. `p` prints
the value of the selected variable or function call result.

    (gdb) up
    (gdb) down
    (gdb) p checkable
    (gdb) p checkable.px->m_Name


### <a id="development-debug-gdb-breakpoint"></a> GDB Breakpoints

To set a breakpoint to a specific function call, or file specific line.

    (gdb) b checkable.cpp:125
    (gdb) b icinga::Checkable::SetEnablePerfdata

GDB will ask about loading the required symbols later, select `yes` instead
of `no`.

Then run Icinga 2 until it reaches the first breakpoint. Continue with `c`
afterwards.

    (gdb) run
    (gdb) c

If you want to delete all breakpoints, use `d` and select `yes`.

    (gdb) d