Chef

Overview

Chef is a popular configuration management tool written in Ruby and Erlang.

Deploying Datadog with Chef is meant to be very simple, and provide you with a method of getting the value of monitoring across all of your infrastructure as simply as possible.

Datadog also provides a Chef Execution and Report Handler that can capture chef-client failures as well as metrics related to the Chef run, such as timing and resources updated.

Setup

Deploying the Agent

The Datadog Chef cookbook is available to automate your Datadog Agent installation and configuration.

Install the latest released version of the Datadog Chef cookbook from the Supermarket with knife, and upload to your Chef Server:

knife cookbook site install datadog
knife cookbook upload datadog

And follow the instructions for your tool to upload the cookbook to your Chef Server.

Before adding the cookbook’s recipe to your node’s run_list, you must add your Datadog account credentials such as API keys using Chef attributes.

This is commonly done with role or environment files, or another cookbook declaring the attributes.

Here is an example of a base.rb role file, typically applied to every host in an organization.

name 'base'
description 'base role, runs on every node'
run_list(
  'ntp',
  'datadog::dd-agent',
  'some_other_base_cookbook::recipe'
)
default_attributes(
  'datadog' => {
    'api_key' => "PUT_YOUR_API_KEY_HERE",
    'application_key' => "PUT_YOUR_APPLICATION_KEY_HERE"
  }
)

Note: There are two keys needed. Your Datadog API key and application key.

Provide both values in the attributes as shown above.

Then upload your role file to Chef Server like so:

knife role from file roles/base.rb

The next time Chef runs, it installs the Agent and sets the configuration file with the API and application keys.

NOTE: If you are using another cookbook to define these attributes, use a higher attribute precedence level than default.

Report handler

Datadog offers a Chef report handler which reports metrics and events from your Chef runs to Datadog. Once installed the report handler submits metrics on Chef run timing and resource changes. Events are also created to allow tracking of Chef run success and failure rates.

This has the added value of bringing the output of a Chef run back to Datadog’s Event stream, so failures can be highlighted quickly, discussed amongst the team, and resolved.

Successes are found under “Low” priority, whereas failures are of “Normal” priority, and when the same node passes the Chef run, then it is put pack into “Low” priority.

Adding the handler is very simple, as you can see in this role snippet:

name 'base'
description 'base role, runs on every node'
run_list(
  'datadog::dd-handler',
  'ntp',
  'datadog::dd-agent',
  'some_other_base_cookbook::recipe'
)
default_attributes(
  'datadog' => {
    'api_key' => "<DATADOG_API_KEY>",
    'application_key' => "<DATADOG_APPLICATION>"
  }
)

In this example, the datadog::dd-handler recipe was added to the beginning of the node’s run list. Adding it to the beginning allows the handler to capture details about everything in it observes after being invoked, so if you added it to the end of the run_list and something failed prior to it being executed, you may not receive the full output.

Once set, upload the role to your Chef Server, and wait. After Chef has run on a few hosts, a new automatic Dashboard is created, with the relevant Chef metrics. You can find it in your Dashboards List, on the right-hand side.

Sending Chef metrics to Datadog.

If you are using Berkshelf, add the cookbook to your Berksfile:
```
cookbook 'datadog'
```
Otherwise, install the cookbook in to your repository using Knife:
```
knife cookbook site install datadog
```

Set the Datadog-specific attributes in either a role, environment or another recipe:

# Make sure you replace the API and application key below
# with the ones for your account

node.default['datadog']['<API_KEY>'] = "<DATADOG_API_KEY>"

# Use an existing application key or create a new one for Chef
node.default['datadog']['<APPLICATION_KEY>] ="<DATADOG_APP_KEY>"

Upload the updated cookbook to your Chef server

berks upload
# or
knife cookbook upload datadog

knife cookbook list | grep datadog && \
echo -e "\033[0;32mdatadog cookbook - OK\033[0m" || \
echo -e "\033[0;31mmissing datadog cookbook - OK\033[0m"

The cookbook is ready to be applied to your nodes.

Once uploaded, add it to your node’s run_list or role:
```
"run_list": [
  "recipe[datadog::dd-handler]"
]
```
Wait for the next scheduled chef-client run.

Log collection

Log collection is available with Agent v6.0+, see attributes/default.rb to enable it. For more details, see the setup example below.

Validation

From your events stream, enter sources:chef in the search bar. Your Chef runs should appear.

Data Collected

Metrics

chef.resources.elapsed_time (gauge)	Total time elapsed during the Chef Client Run. Shown as second
chef.resources.total (gauge)	Total count of resources managed by Chef. Shown as resource
chef.resources.updated (gauge)	Total count of resources updated in the Chef Client Run. Shown as resource

name 'webserver'
description 'Webserver role, runs apache'
run_list(
  'apache2',
  'datadog::apache',
)
default_attributes(
  'apache' => {
    'ext_status' => true,
  }
  'datadog' => {
    'apache' => {
      'instances' => [
        { 'status_url' => 'http://localhost:8080/server-status/',
          'tags' => ['extra_tag', 'env:example'] }
      ],
      'logs' => [
        { 'type' => 'file',
          'path' => '/var/log/apache2/access.log',
          'source' => 'apache',
          'service' => 'myapp',
          'sourcecategory' => 'http_web_access',
          'tags' => ['extra_tag', 'env:example'] },
        { 'type' => 'file',
          'path' => '/var/log/apache2/error.log',
          'source' => 'apache',
          'service' => 'myapp',
          'sourcecategory' => 'http_web_access',
          'tags' => ['extra_tag', 'env:example'] }
      ]
    }
  }
)

In this example, the datadog::apache recipe was added to the run list along with some attributes to control what instances of Apache should be monitored by Datadog.

Read each recipe file for the exact details of the integration values to pass into the instances part of the attributes.