Configuration

There are several ways to configure how Elastic APM behaves. The recommended way is to specify options in a config/elastic_apm.yml file:

server_url: 'http://localhost:8200'
secret_token: <%= ENV["VERY_SECRET_TOKEN"] %>

Some options can be set with ENV variables. When using this method, strings are split by comma, e.g., ELASTIC_APM_SANITIZE_FIELD_NAMES="a,b" # => [/a/, /b/].

Options are applied in the following order (last one wins):

Configuration options marked with the badge can be changed at runtime when set from a supported source.

The Agent supports Central configuration, which allows you to fine-tune certain configurations via the APM app. This feature is enabled in the Agent by default, with central_config.

When using Rails, it’s possible to specify options inside config/application.rb:

# config/application.rb
config.elastic_apm.service_name = 'MyApp'

When using Sinatra and Rack, you can configure when starting the agent:

# config.ru or similar
ElasticAPM.start(
  app: MyApp,
  service_name: 'SomeOtherName'
)

Alternatively, you can use the ElasticAPM::Sinatra.start API:

# config.ru or similar
ElasticAPM::Sinatra.start(
  MyApp,
  service_name: 'SomeOtherName'
)

See Getting started with Rack.

When using Grape and Rack (without Rails), you can configure when starting the agent:

# config.ru or similar
ElasticAPM::Grape.start(
  MyApp,
  service_name: 'SomeOtherName'
)

See Getting started with Rack.

Path to the configuration YAML-file. Elastic APM will load config options from this if the file exists. The file will be evaluated as ERB, so you can include ENV variables like in your database.yml, eg:

secret_token: <%= ENV['VERY_SECRET_TOKEN'] %>

The URL for your APM Server. The URL must be fully qualified, including protocol (http or https) and port.

This string is used to ensure that only your agents can send data to your APM server. Both the agents and the APM server have to be configured with the same secret token. One example to generate a secure secret token is:

ruby -r securerandom -e 'print SecureRandom.uuid'

This base64-encoded string is used to ensure that only your agents can send data to your APM server. You must have created the api key using the APM server command line tool. Please see the APM server documentation for details on how to do that. Please note that this feature is experimental in the APM server in version 7.6.

Whether or not to start the agent. If active is false, ElasticAPM.start will do nothing and all calls to the root API will return nil.

Maximum amount of objects kept in queue, before sending to APM Server.

If you hit this limit you either have to increase the agent’s worker pool size or it could mean the agent has trouble connecting to APM Server. The logs should tell you what went wrong.

Maximum amount of bytes sent over one request to APM Server. When reached the agent will open a new request.

It has to be provided in size format.

Maximum duration of a single streaming request to APM Server before opening a new one.

APM Server has its own limit of 30 seconds before it will close requests.

It has to be provided in duration format.

Enable/disable the tracking and collection of breakdown metrics. By setting this to False, tracking this metric is completely disabled, which can reduce the overhead of the agent.

For transactions that are HTTP requests, the Ruby agent can optionally capture the request body (e.g. POST variables or JSON data).

Possible values: "errors", "transactions", "all", "off".

If the request has a body and this setting is disabled, the body will be shown as [SKIPPED].

Whether or not to attach the request headers to transactions and errors.

Whether or not to capture the body from requests in Elasticsearch.

Whether or not to attach ENV from Rack to transactions and errors.

Enables APM Agent Configuration via Kibana. If set to true, the client will poll the APM Server regularly for new agent configuration.

Usually APM Server determines how often to poll, but if not the default interval is 5 minutes.

Specify the cloud provider for metadata collection. Defaults to "auto", which means the agent uses trial and error to collect metadata from all supported cloud providers.

Valid options are "auto", "aws", "gcp", "azure", and "none". If set to "none", no cloud metadata will be collected. If set to any of "aws", "gcp", or "azure", attempts to collect metadata will only be performed from the chosen provider.

Elastic APM strips what looks like confidential information from the request/response headers. Use this option to add your own custom header keys to the list of filtered keys.

When setting this option via ENV, use a comma separated string. Eg. ELASTIC_APM_CUSTOM_KEY_FILTERS="a,b" # => [/a/, /b/]

Add default labels to every transaction. Note that this will eventually be deprecated in favor of global_labels.

Add default tags to add to every transaction. Note that this option has been deprecated in favor of default_labels.

A comma-separated list of dotted metrics names that should not be sent to the APM Server. You can use * to match multiple metrics. Matching is case-insensitive.

Disables sending payloads to APM Server.

Disables the agent’s startup message announcing itself.

Elastic APM automatically instruments select third party libraries. Use this option to disable any of these.

Get an array of enabled instrumentations with ElasticAPM.agent.config.enabled_instrumentations.

Whether or not to start the agent. If enabled is false, ElasticAPM.start will do nothing and all calls to the root API will return nil.

The name of the environment this service is deployed in, e.g. "production" or "staging".

Environments allow you to easily filter data on a global level in the APM app. It’s important to be consistent when naming environments across agents. See environment selector in the APM app for more information.

Defaults to ENV['RAILS_ENV'] || ENV['RACK_ENV'].

Use this to filter error tracking for specific error constants.

Name of the used framework. For Rails or Sinatra, this defaults to Ruby on Rails and Sinatra respectively, otherwise defaults to nil.

Version number of the used framework. For Ruby on Rails and Sinatra, this defaults to the used version of the framework, otherwise, the default is nil.

Labels added to all events, with the format key=value[,key=value[,…​]].

The host name to use when sending error and transaction data to the APM server.

Use this option to ignore certain URL patterns eg. healthchecks or admin sections.

Ignoring in this context means don’t wrap in a Transaction. Errors will still be reported.

When setting this option via ENV, use a comma separated string. Eg. ELASTIC_APM_IGNORE_URL_PATTERNS="a,b" # => [/a/, /b/]

Use this option to ignore certain URL patterns eg. healthchecks or admin sections.

Elastic APM can instrument your Rake tasks but given that they are used for a multitude of sometimes very different and not always relevant things, this is opt in.

By default Elastic APM logs to stdout or uses Rails.log when used with Rails.

A path to a log file.

By default Elastic APM logs to stdout or uses Rails.log when used with Rails.

Should support both absolute and relative paths. Just make sure the directory exists.

By default Elastic APM logs to stdout or uses Rails.log when used with Rails.

Use this to provide another logger. Expected to have the same API as Ruby’s built-in Logger.

Specify the interval for reporting metrics to APM Server. The interval should be in seconds, or should include a time suffix.

To disable metrics reporting, set the interval to 0.

Elastic APM uses a thread pool to send its data to APM Server.

This makes sure the agent doesn’t block the main thread any more than necessary.

If you have high load and get warnings about the buffer being full, increasing the worker pool size might help.

An address to use as a proxy for the HTTP client.

Options available are:

There are also ENV version of these following the same pattern of putting ELASTIC_APM_ in front.

See Http.rb’s docs.

Enable or disable the recording of events. If set to false, then the agent does not create or send any events to the Elastic APM server, and instrumentation overhead is minimized. The agent continues to poll the server for configuration changes when this option is false.

Sometimes it is necessary to sanitize the data sent to Elastic APM, e.g. remove sensitive data.

Configure a list of wildcard patterns of field names which should be sanitized. These apply to HTTP headers and bodies (if you’re capturing those.)

Supports the wildcard *, which matches zero or more characters. Examples: /foo/*/bar/*/baz*, *foo*. Matching is case insensitive.

The name of your service. This is used to keep all the errors and transactions of your service together and is the primary filter in the Elastic APM user interface.

If you’re using Ruby on Rails this will default to your app’s name. If you’re using Sinatra it will default to the name of your app’s class.

[options="header"]

The name of the given service node. This is optional, and if omitted, the APM Server will fall back on system.container.id if available, and finally host.name if necessary.

This option allows you to set the node name manually to ensure uniqueness and meaningfulness.

Deployed version of your service. Defaults to git rev-parse --verify HEAD.

By default, the APM agent collects source code snippets for errors. With the above settings, you can modify how many lines of source code is collected.

We differ between errors and spans, as well as library frames and app frames.

Use this to disable stacktrace frame collection for spans with a duration shorter than or equal to the given amount of milleseconds.

The default is "5ms".

Set it to -1 to collect stack traces for all spans. Set it to 0 to disable stack trace collection for all spans.

It has to be provided in duration format.

The path to a custom CA certificate for connecting to APM Server.

The maximum number of stack trace lines per span/error.

Limits the amount of spans that are recorded per transaction. This is helpful in cases where a transaction creates a very high amount of spans (e.g. thousands of SQL queries). Setting an upper limit will prevent overloading the agent and the APM server with too much work for such edge cases.

By default, the agent will sample every transaction (e.g. request to your service). To reduce overhead and storage requirements, you can set the sample rate to a value between 0.0 and 1.0. We still record overall time and the result for unsampled transactions, but no context information, tags, or spans. Note that the sample rate will be rounded to 4 digits of precision.

Use the older, less precise approach to generating summaries of your app’s SQL statements. Try this if you’re experiencing trouble using the new default.

By default, the agent verifies the SSL certificate if you use an HTTPS connection to the APM server. Verification can be disabled by changing this setting to false.

Some options require a unit, either duration or size. These need to be provided in a specific format.

The duration format is used for options like timeouts. The unit is provided as suffix directly after the number, without any separation by whitespace.

Example: "5ms"

Supported units

The size format is used for options like maximum buffer sizes. The unit is provided as suffix directly after the number, without any separation by whitespace.

Example: 10kb

Supported units:

Elastic APM patches Kernel#require to auto-detect and instrument supported third party libraries. It does so with the utmost care but in rare cases it can conflict with some libraries.

To get around this patch, set the environment variable ELASTIC_APM_SKIP_REQUIRE_PATCH to "1".

If you choose to do so, the agent might need some additional tweaking to make sure the third party libraries are picked up and instrumented. Make sure you require the agent after you require your other dependencies.