Health API Calls
Health Read API#
Enabled Alarms#
Netdata enables alarms on demand, i.e. when the chart they should be linked to starts collecting data. So, although many more alarms are configured, only the useful ones are enabled.
To get the list of all enabled alarms, open your browser and navigate to http://NODE:19999/api/v1/alarms?all,
replacing NODE with the IP address or hostname for your Agent dashboard.
Raised Alarms#
This API call will return the alarms currently in WARNING or CRITICAL state.
http://NODE:19999/api/v1/alarms
Event Log#
The size of the alarm log is configured in netdata.conf. There are 2 settings: the rotation of the alarm log file and the in memory size of the alarm log.
The API call retrieves all entries of the alarm log:
http://NODE:19999/api/v1/alarm_log
Alarm Log Incremental Updates#
http://NODE:19999/api/v1/alarm_log?after=UNIQUEID
The above returns all the events in the alarm log that occurred after UNIQUEID (you poll it once without after=, remember the last UNIQUEID of the returned set, which you give back to get incrementally the next events).
Alarm badges#
The following will return an SVG badge of the alarm named NAME, attached to the chart named CHART.
http://NODE:19999/api/v1/badge.svg?alarm=NAME&chart=CHART
Health Management API#
Netdata v1.12 and beyond provides a command API to control health checks and notifications at runtime. The feature is especially useful for maintenance periods, during which you receive meaningless alarms. From Netdata v1.16.0 and beyond, the configuration controlled via the API commands is persisted across Netdata restarts.
Specifically, the API allows you to:
- Disable health checks completely. Alarm conditions will not be evaluated at all and no entries will be added to the alarm log.
- Silence alarm notifications. Alarm conditions will be evaluated, the alarms will appear in the log and the Netdata UI will show the alarms as active, but no notifications will be sent.
- Disable or Silence specific alarms that match selectors on alarm/template name, chart, context, host and family.
The API is available by default, but it is protected by an api authorization token that is stored in the file you will see in the following entry of http://NODE:19999/netdata.conf:
You can access the API via GET requests, by adding the bearer token to an Authorization http header, like this:
By default access to the health management API is only allowed from localhost. Accessing the API from anything else will return a 403 error with the message You are not allowed to access this resource.. You can change permissions by editing the allow management from variable in netdata.conf within the [web] section. See web server access lists for more information.
The command RESET just returns Netdata to the default operation, with all health checks and notifications enabled.
If you've configured and entered your token correctly, you should see the plain text response All health checks and notifications are enabled.
Disable or silence all alarms#
If all you need is temporarily disable all health checks, then you issue the following before your maintenance period starts:
The effect of disabling health checks is that the alarm criteria are not evaluated at all and nothing is written in the alarm log. If you want the health checks to be running but to not receive any notifications during your maintenance period, you can instead use this:
Alarms may then still be raised and logged in Netdata, so you'll be able to see them via the UI.
Regardless of the option you choose, at the end of your maintenance period you revert to the normal state via the RESET command.
Disable or silence specific alarms#
If you do not wish to disable/silence all alarms, then the DISABLE ALL and SILENCE ALL commands can't be used.
Instead, the following commands expect that one or more alarm selectors will be added, so that only alarms that match the selectors are disabled or silenced.
DISABLE: Set the mode to disable health checks.SILENCE: Set the mode to silence notifications.
You will normally put one of these commands in the same request with your first alarm selector, but it's possible to issue them separately as well. You will get a warning in the response, if a selector was added without a SILENCE/DISABLE command, or vice versa.
Each request can specify a single alarm selector, with one or more selection criteria.
A single alarm will match a selector if all selection criteria match the alarm.
You can add as many selectors as you like.
In essence, the rule is: IF (alarm matches all the criteria in selector1 OR all the criteria in selector2 OR ...) THEN apply the DISABLE or SILENCE command.
To clear all selectors and reset the mode to default, use the RESET command.
The following example silences notifications for all the alarms with context=load:
Selection criteria#
The selection criteria are key/value pairs, in the format key : value, where value is a Netdata simple pattern. This means that you can create very powerful selectors (you will rarely need more than one or two).
The accepted keys for the selection criteria are the following:
alarm: The expression provided will match bothalarmandtemplatenames.chart: Chart ids/names, as shown on the dashboard. These will match theonentry of a configuredalarm.context: Chart context, as shown on the dashboard. These will match theonentry of a configuredtemplate.hosts: The hostnames that will need to match.families: The alarm families.
You can add any of the selection criteria you need on the request, to ensure that only the alarms you are interested in are matched and disabled/silenced. e.g. there is no reason to add hosts: *, if you want the criteria to be applied to alarms for all hosts.
Example 1: Disable all health checks for context = random
Example 2: Silence all alarms and templates with name starting with out_of on host myhost
Example 2.2: Add one more selector, to also silence alarms for cpu1 and cpu2
List silencers#
The command LIST was added in Netdata v1.16.0 and returns a JSON with the current status of the silencers.
As an example, the following response shows that we have two silencers configured, one for an alarm called samplealarm and one for alarms with context random on host myhost
The response below shows that we have disabled all health checks.
Responses#
- "Auth Error" : Token authentication failed
- "All alarm notifications are silenced" : Successful response to cmd=SILENCE ALL
- "All health checks are disabled" : Successful response to cmd=DISABLE ALL
- "All health checks and notifications are enabled" : Successful response to cmd=RESET
- "Health checks disabled for alarms matching the selectors" : Added to the response for a cmd=DISABLE
- "Alarm notifications silenced for alarms matching the selectors" : Added to the response for a cmd=SILENCE
- "Alarm selector added" : Added to the response when a new selector is added
- "Invalid key. Ignoring it." : Wrong name of a parameter. Added to the response and ignored.
- "WARNING: Added alarm selector to silence/disable alarms without a SILENCE or DISABLE command." : Added to the response if a selector is added without a selector-specific command.
- "WARNING: SILENCE or DISABLE command is ineffective without defining any alarm selectors." : Added to the response if a selector-specific command is issued without a selector.
Persistence#
From Netdata v1.16.0 and beyond, the silencers configuration is persisted to disk and loaded when Netdata starts.
The JSON string returned by the LIST command is automatically saved to the silencers file, every time a command alters the silencers configuration.
The file's location is configurable in netdata.conf. The default is shown below:
Further reading#
The test script under tests/health_mgmtapi contains a series of tests that you can either run or read through to understand the various calls and responses better.