answers.md

Level 1

Regristration

Adress mail : [email protected]

What is the agent ?

The agent is a software that watch for metrics on your machine and send it to datadog.

Event API

require 'rubygems'
require 'dogapi'
api_key='...'
dog = Dogapi::Client.new(api_key)
dog.emit_event(Dogapi::Event.new('Hello dog !', :msg_title => 'Hello'))

Event API with email

require 'rubygems'
require 'dogapi'
api_key='...'
dog = Dogapi::Client.new(api_key)
dog.emit_event(Dogapi::Event.new('What if @[email protected] ?', :msg_title => 'Mailing with mention'))

Level 2

For this par I took a local web app in Ruby on Rails with 4 public pages

• demoreel (root)
• production
• resume
• contact

I used the level2-tsung.xml file for load test

### Page views count & latency I've added some code in my static_pages_controller.rb

class StaticPagesController < ApplicationController
  require 'statsd'
  layout false

  def contact
    start = Time.now
    s = Statsd.new
    s.increment('web.page_views')
    render 'contact'
    lag = Time.now - start
    s.histogram('latency', lag)
  end

# [...]
# Similar for demoreel, production and resume function

end

I'm quite surprise by the result of the page views per second. There is none sometimes whereas there are some page views. .

Level 3

### Tagging metrics

To tag metrics all metrics I've introduced a variable in my controller

common_tags = ["support"]

Then in each function I've introduced the specific tag

  def contact
    start = Time.now
    s = Statsd.new
    tags = Array.new(common_tags).push("page:contact")
    s.increment('web.page_views', :tags => tags)
    render 'contact'
    lag = Time.now - start
    s.histogram('latency', lag, :tags => tags)
  end

Level 4

### Overall number of page views and by page

Level 5

Agent check that samples a random values

First we need to create a random_check.yaml in /etc/dd-agent/conf.d/

init_config:

instances:
  [{}]

Then random_check.py in /etc/dd-agent/checks.d/

from checks import AgentCheck
import random

class random_check(AgentCheck):
  def check(self,instance):
    self.gauge('test.support.random' , random.random())

And we restrat with sudo /etc/init.d/datadog-agent restart

Visualize it