Prometheus data source reference

This is a general description of Prometheus data source-based extension YAML file and ways to declare metrics and dimensions you would like to collect using your extension.

Data scope

Create an inventory of Prometheus endpoints you'd like to reference in your extension, as well as metrics and dimension values.

In our example, we create a simple extension collecting Rabbit MQ metrics.

name: com.dynatrace.extension.prometheus-rabbitmq
version: 1.0.0
minDynatraceVersion: '1.236'
author:
name: Dynatrace
dashboards:
- path: 'dashboards/dashboard_exporter.json'
alerts:
- path: 'alerts/alert_socket_usage.json'
# Extension based on official rabbitmq prometheus exporter available metrics
# list of metrics visible here https://github.com/rabbitmq/rabbitmq-server/blob/master/deps/rabbitmq_prometheus/metrics.md
prometheus:
- group: rabbitmq metrics
interval:
minutes: 1
featureSet: all
dimensions:
- key: rabbitmq
value: const:rabbitmq
subgroups:
# global counters
- subgroup: rabbitmq global counter
dimensions:
- key: global_counters
value: const:global_counters
metrics:
- key: com.dynatrace.extension.prometheus-rabbitmq.global.global_messages_acknowledged_total
value: metric:rabbitmq_global_messages_acknowledged_total
type: count
featureSet: global
- key: com.dynatrace.extension.prometheus-rabbitmq.global.global_messages_confirmed_total
value: metric:rabbitmq_global_messages_confirmed_total
type: count
featureSet: global
- key: com.dynatrace.extension.prometheus-rabbitmq.global.global_messages_delivered_consume_auto_ack_total
value: metric:rabbitmq_global_messages_delivered_consume_auto_ack_total
type: count
featureSet: global

Your Prometheus monitoring scope definition starts with the prometheus YAML node. All the settings under the node pertain to the declared data source type (in this case, Prometheus).

Dimensions

For each level (group, subgroup), you can define up to 25 dimensions (which gives you a total of 50 dimensions per metric).

Dimension key

The dimension key string must conform to the metrics ingestion protocol.

Dimension value

You can use the following methods to define dimensions for your metrics:

  • Plain text. Prefix with const: or simply add the required text
    dimensions:
    - key: extension.owner
    value: const:Joe.Doe@somedomain.com
    or
    dimensions:
    - key: extension.owner
    value: Joe.Doe@somedomain.com
  • Prometheus label
    dimensions:
    - key: customdimension.job
    value: label:job
    filter: const:$eq(prometheus)
    All the labels exposed by Prometheus are created as dimensions automatically. You only need to explicitly define a label-based dimension if you want to:
    • apply filtering on the values,
    • define a custom dimension key.

Filter extracted metric lines

When extracting metric lines, you can add filtering logic that will result in reporting only the lines for which the dimension value matches the filtering criteria.

Define the filter based on a condition as follows:

  • Starts with – use a const:$prefix qualifier. Example:

    filter: const:$prefix(xyz)
  • Ends with – use a const:$suffix qualifier. Example:

    filter: const:$suffix(xyz)
  • Contains – use a const:$contains qualifier. Example:

    filter: const:$contains(xyz)
  • Equals – use a const:$eq qualifier. Example:

    filter: const:$eq(xyz)

    For the expressions mentioned above, you can also use qualifiers:

    • const:$and – to chain two or more expressions with AND operator. Example:
      filter: const:$and(<expr1>,<expr2>)
    • a const:$or – to chain two or more expressions with OR operator. Example:
      filter: const:$or(<expr1>,<expr2>)
    • a const:$not – to negate an expression. Example:
      filter: const:$not(<expr>)

You can create complex filters by combining two or more filters separated by commas using logical expressions:

dimensions:
- key: technology
value: other
- key: job
value: label:job
filter: const:$or($eq(),$not($or($eq(prometheus),$eq(rabbitmq-server),$eq(redis_exporter),$eq(node_exporter)))

Metrics

For each level (group, subgroup), you can define up to 100 metrics. Note, however, that there is a hard limit of 1,000 metrics per extension applied at runtime. This limit is lower than the combined limits of allowed groups and subgroups.

For example:

prometheus:
- group: rabbitmq metrics
interval: 1m
featureSet: all
dimensions:
- key: instance
value: $reference(metric:rabbitmq_identity_info, ref:rabbitmq_node)
subgroups:
# global counters
- subgroup: rabbitmq global counter
metrics:
- key: com.dynatrace.extension.prometheus-rabbitmq.global.global_messages_acknowledged_total
value: metric:rabbitmq_global_messages_acknowledged_total
type: count
featureSet: global
- key: com.dynatrace.extension.prometheus-rabbitmq.global.global_messages_confirmed_total
value: metric:rabbitmq_global_messages_confirmed_total
type: count
featureSet: global

Metric key

The metric key string must conform to the metrics ingestion protocol.

For Dynatrace versions 1.215 and 1.217, a metric node requires the id parameter in place of key. Starting with Dynatrace version 1.219, we recommend that you use the key parameter, as id will be deprecated.

Best practices for metric keys

The metrics you ingest into Dynatrace using your extension are just some of the thousands of metrics, built-in and custom, processed by Dynatrace. To make your metrics keys unique and easy to identify in Dynatrace, the best practice is to prefix the metric name with the extension name. This guarantees that the metric key is unique and you can easily appoint a metric to a particular extension in your environment.

Metric value

The Prometheus metric key from which you want to extract the metric value prefixed with metric:.

Type

The Dynatrace Extensions 2.0 framework supports all original Prometheus metric payload formats. For details, see Metric payload. To indicate the metric type, use the type attribute.

Prometheus exposed type

Dynatrace ingest

  • Count part as <metric-key>_count
  • Total sum part as <metric-key>_sum.count
  • Individual buckets split by the le dimension indicating the bucket identifier as <metric-key>_bucket.count

Individual bucket metrics ingestion is disabled by default. For details on how to enable it, refer to the advanced extension monitoring configuration description.

A standard Prometheus histogram metric includes:

  • HELP and TYPE
  • Bucket data and summary metrics for sum and count
# HELP http_response_time_seconds Time to respond to request
# TYPE http_response_time_seconds histogram
http_response_time_seconds_bucket{code="200",method="GET",path="/banners/post-auth",service="platform",le="0.005"} 1
...
http_response_time_seconds_sum{code="404",method="POST",path="/revoke",service="platform"} 0.016945976
http_response_time_seconds_count{code="404",method="POST",path="/revoke",service="platform"} 1

You can define metric metadata in the extensions.yaml file as shown below:

metrics:
- key: http_response_time_seconds_count
metadata:
displayName: HTTP response time (Histogram count of observed events)
description: Time to respond to request
- key: http_response_time_seconds_sum.count
metadata:
displayName: HTTP response time (Histogram total sum of all observed values)
description: Time to respond to request
unit: Second
- key: http_response_time_seconds_bucket.count
metadata:
displayName: HTTP response time (Histogram buckets split by le)
description: Time to respond to request
unit: Second

To ingest histogram metrics in the Prometheus data source section of the extensions.yaml file:

  • Use the base name of the metric without any summary suffix
  • Specify the type as histogram
prometheus:
- group: CipherTrust Metrics
subgroups:
- subgroup: HTTP Traffic
featureSet: HTTP_Traffic
metrics:
- key: http_response_time_seconds
value: metric:http_response_time_seconds
type: histogram
  • Count part as <metric-key>_count
  • Total sum part as <metric-key>_sum.count
  • Individual quantiles split by the quantile dimension indicating the quantile as <metric-key>

Metric metadata

An Extension can define metadata for each metric available in Dynatrace. For example, you might want to add the metric display name and the unit, both of which can be used for filtering in the Metrics browser.

name: custom:example-extension-name
version: 1.0.0
minDynatraceVersion: "1.236"
author:
name: Dynatrace
metrics:
- key: your.metric.name
metadata:
displayName: Display name of the metric visible in Metrics browser
unit: Count

Feature set

Feature sets are categories into which you organize the data collected by the extension. You can define feature sets at the group, subgroup, or metric level. In this example, we create a Prometheus extension collecting application and network metrics. This is reflected by metrics organization into related feature sets prometheus_app_metrics and prometheus_net_metrics.

prometheus:
- group: prometheus metrics
interval: 1m
metrics:
- key: com.dynatrace.extension.prometheus.app
value: prometheus.app
featureSet: prometheus_app_metrics
- key: com.dynatrace.extension.prometheus.net
value: prometheus.net
featureSet: prometheus_net_metrics

When activating your extension using monitoring configuration, you can limit monitoring to one of the feature sets. To work properly the extension has to collect at least one metric after the activation.

In highly segmented networks, feature sets can reflect the segments of your environment. Then, when you create a monitoring configuration, you can select a feature set and a corresponding ActiveGate group that can connect to this particular segment.

All metrics that aren't categorized into any feature set are considered to be the default and are always reported.

A metric inherits the feature set of a subgroup, which in turn inherits the feature set of a group. Also, the feature set defined on the metric level overrides the feature set defined on the subgroup level, which in turn overrides the feature set defined on the group level.

Interval

The interval at which the data measurement will be taken. You can define intervals at the group, subgroup, or individual metric level. You can define intervals with the granularity of one minute. The maximum interval is 2880 minutes (2 days, 48 hours).

Setting the interval is not possible for JMX data sources.

For example:

interval:
minutes: 5

The above format is supported starting with schema version 1.217. For earlier schema versions, use the following format (supported up to schema version 1.251):

interval: 5m
prometheus:
- group: prometheus metrics
interval: 1m
dimensions:
- key: technology
value: prometheus
metrics:
- key: com.dynatrace.extension.prometheus-rabbitmq.global.global_messages_delivered_get_auto_ack_total
value: metric:rabbitmq_global_messages_delivered_get_auto_ack_total
type: count

A metric inherits the interval of a subgroup, which in turn inherits the interval of a group. Also, the interval defined on the metric level overrides the interval defined on the subgroup level, which in turn overrides the interval defined on the group level.

Monitoring configuration

After you define the scope of your configuration, you need to identify the Prometheus endpoints from which to collect data.

The monitoring configuration is a JSON payload defining the connection details, credentials, and feature sets that you want to monitor. For details, see Start monitoring.

Example payload to activate a Prometheus extension:

[
{
"scope": "ag_group-default",
"value": {
"version": "1.0.0",
"description": "name",
"enabled": true,
"activationContext": "REMOTE",
"prometheusRemote": {
"endpoints": [
{
"url": "https://myPrometheusServer/metrics",
"authentication": {
"scheme": "basic",
"username": "user",
"password": "password"
}
"autoDiscovery": [
{
"autoDiscoveryType": "dns_sd_config",
"dnsType": "a",
"dnsPort": 1111,
"refreshInterval": "30"
}
]
}
]
},
"featureSets": [
"myFeatureSet"
]
}
}
]

When you have your initial extension YAML ready, package it, sign it, and upload it to your Dynatrace environment. For details, see Manage extension lifecyle.

The Dynatrace Hub-based extension activation wizard contains a dynamically updated JSON payload with your monitoring configuration.

You can also use the Dynatrace API to download the schema for your extension that will help you create the JSON payload for your monitoring configuration.

Use the GET an extension schema endpoint.

Issue the following request:

curl -X GET "{env-id}.live.dynatrace.com/api/v2/extensions/{extension-name}/{extension-version}/schema" \
-H "accept: application/json; charset=utf-8" \
-H "Authorization: Api-Token {api-token}"

Make sure to replace {extension-name} and {extension-version} with values from your extension YAML file. A successful call returns the JSON schema.

Scope

Note that each OneAgent or ActiveGate host running your extension needs the root certificate to verify the authenticity of your extension. For more information, see Sign extension.

For a remote extension, the scope is an ActiveGate group that will execute the extension. Only one ActiveGate from the group will run this monitoring configuration. If you plan to use a single ActiveGate, assign it to a dedicated group. You can assign an ActiveGate to a group during or after installation. For more information, see ActiveGate group.

Use the following format when defining the ActiveGate group:

"scope": "ag_group-<ActiveGate-group-name>",

Replace <ActiveGate-group-name> with the actual name.

Local extension

For a local extension, the scope is a host, host group, or management zone for which you will execute the extension. You can also select to monitor your whole environment (optionally, limited by tags).

  • When defining a host as the scope, use this format:
    "scope": "<HOST_ID>",
    Replace <HOST_ID> with the entity ID of the host as in this example:
    "scope": "HOST-A1B2345678C9D001",
  • When defining a host group as the scope, use this format:
    "scope": "HOST_GROUP-<HOST_GROUP_ID>",
    Replace <HOST_GROUP_ID> with the entity ID of the host group as in this example:
    "scope": "HOST_GROUP-AB123C4D567E890",
    You can find the host group ID on the host group settings page URL. For example:
    https://{your-environment-id}.live.dynatrace.com/#settings/hostgroupconfiguration;id=HOST_GROUP-AB123C4D567E890;hostGroupName=my-host-group
  • When defining a management zone as the scope, use this format:
    "scope": "management_zone-<MANAGEMENT-ZONE>",
    Replace <MANAGEMENT-ZONE> with the management zone name as in this example:
    "scope": "management_zone-sampleManagementZone",
    You can find the management zone on the Management zones settings page.
  • When defining an environment as the scope, use this format:
    "scope": "environment",
    You can also add tags to filter the hosts this configuration will run on:
    "activationTags": [
    "dt.owner:lama"
    ]

If you activate a local Prometheus extension and define the endpoint of a Prometheus Server running on the same host, the metrics gathered from that server may come from various endpoints, not only from the endpoint on that host, but all the metrics will be enriched with the OneAgent-installed host context.

Version

The version of this monitoring configuration. Note that a single extension can run multiple monitoring configurations.

Description

A human-readable description of the specifics of this monitoring configuration.

Enabled

If set to true, the configuration is active and Dynatrace starts monitoring immediately.

Activation context

  • For remote extensions, set activationContext to REMOTE
  • For local extensions, set activationContext to LOCAL

URL

The URL is the Prometheus endpoint from which your extension pulls the metrics. The maximum URL length is 500 characters.

  • For local extensions, define the Prometheus endpoint in the prometheusLocal node.
  • For remote extensions, define the Prometheus endpoint in the prometheusRemote node.

You can define the following endpoint types:

  • /metrics – returns metrics in plain text Prometheus format.
  • /api/v1/ – API path that could be followed directly by a query or metadata endpoint.

If you gather the same metrics from different endpoints (either Prometheus server or data exporter), some metrics could be overwritten, as the keys would be identical regardless of the endpoint. To avoid this, we automatically add an extra activation_endpoint dimension to each metric.

Authentication

Authentication details passed to Dynatrace API when activating monitoring configuration are obfuscated and it's impossible to retrieve them.

No authentication

By default, supported only for HTTP endpoints.

"authentication": {
"scheme": "none"
}

Bearer

Bearer authentication requires the token only.

"authentication": {
"scheme": "bearer",
"token": "myToken"
}

Basic

Basic authentication requires only a username and password.

"authentication": {
"scheme": "basic",
"username": "user",
"password": "password"
}

AWS - requires AWS access key, secret key, and region.

AWS authentication requires AWS access key, secret key, and region.

"authentication": {
"scheme": "aws",
"accessKey": "accessKey",
"secretKey": "secretKey",
"region": "us-east-2"
}

If you try to use an HTTP endpoint with a bearer, basic, or AWS schema, the extension framework throws an error to avoid sending sensitive data over an unsafe connection. If, however, you're sure you can do so, set the skipVerifyHttps property to true.

"authentication": {
"scheme": "basic",
"username": "user",
"password": "password",
"skipVerifyHttps": "true"
}

Credential vault

Remote monitoring only

The credential vault authentication type provides a more secure approach to using extensions by securely storing and managing user credentials. To use this, you must be the owner of the credentials and have a credential vault that meets the following criteria:

  • Credential type—User and password
  • Credential scope—Synthetic (in case of external vault usage) and Extension authentication scopes enabled
  • Owner access only is enabled only for credential owners
"authentication": {
"scheme": "basic",
"useCredentialVault": true,
"skipVerifyHttps": false,
"credentialVaultId": "some-credential-vault-id"
}

SSL

For SSL communication between Prometheus and Prometheus exporters, the certificate from the Prometheus host must be added to the operating system trust store on the ActiveGate machines running the extension.

Refer to your operating system-specific documentation on how to add certificate to your operating system trust store.

Feature sets

Add a list of feature sets you want to monitor. To report all feature sets, add all.

"featureSets": [
"basic",
"advanced"
]

Advanced

Optionally, you can define advanced settings controlling the HTTP connection to your Prometheus endpoints:

  • timeoutSecs
    An integer between 0 and 50. The number of seconds to wait for a response from the Prometheus endpoint.
  • retries
    The number of connection retries. The maximum number of retries is 3.
  • collectHistogramBuckets
    Enable or disable ingestion of Prometheus histogram metrics buckets.

It is possible to have a maximum of 3 connection retries of 50 seconds each.

Make sure the total waiting time is never longer than the interval you set for your metrics.

Auto Discovery

Remote monitoring only

Autodiscovery is a feature that automatically resolves the DNS endpoints. If autodiscovery is defined, the URL becomes the DNS name.

"configuration": [
{
"configurationType": "dns_sd_config",
"dnsType": "a",
"dnsPort": 1111,
"refreshInterval": "30m"
}
]
  • Auto discovery type: Only the DNS type available.

  • DNS type: The type of DNS query to perform. Only the A type is available, which corresponds to IPv4 addresses.

  • DNS port: Specifies the port assigned to all IPs resolved by the DNS.

  • DNS refresh interval (s): Sets interval time in seconds to the frequently changing IP addresses.

Resource consumption

Resource consumption depends on the number of Prometheus endpoints. The first endpoint consumes 25 MB of RAM and 0.2%–0.5% of CPU. Every following endpoint consumes 0.5 MB of RAM and ~0.2% of CPU.

Endpoints

Average CPU

Max CPU

RAM (MB)

Host (EC2 instance type)

100

1.0%

2.5% (spike at beginning)

60

XS (c5.large)

1

0.2%

0.5% (spike at beginning)

25

XS (c5.large)