This is the continuation for Setup a simple HAproxy config

It explains how to create an Ansible playbook to automate the haproxy configuration.

If you’d like to find out more about Ansible you can read up on it on their website: http://www.ansible.com

---
# Set up and configure an HaProxy server (Ubuntu flavor)
- name: haproxy
  hosts: all
  user: userwithsudoaccess
  sudo: True
  tags: haproxy

  vars_files:
    - "vars/main.yml"

  tasks:

    # haproxy package for Ubuntu
    - include: tasks/haproxy-apt.yml

    # Specific haproxy tasks follow here
    - name: Copy haproxy logrotate file
      action: >
        copy src=files/haproxy.logrotate dest=/etc/logrotate.d/haproxy
        mode=0644 owner=root group=root

    - name: Create haproxy rsyslog configuration
      action: >
        copy src=files/haproxy-rsyslog.conf
        dest=/etc/rsyslog.d/49-haproxy.conf
        mode=0644 owner=root group=root
      notify: restart rsyslog

    - name: Configure system rsyslog
      action: >
        copy src=files/rsyslog.conf
        dest=/etc/rsyslog.conf
        mode=0644 owner=root group=root
      notify: restart rsyslog

    - name: Create haproxy configuration file
      action: >
        template src=templates/haproxy.cfg.j2 dest=/etc/haproxy/haproxy.cfg
        mode=0644 owner=root group=root
      notify: restart haproxy

The following file that contains the variables needed for the haproxy playbook it should located under vars (vars/main.yml)

---
haproxy_port: 8080
haproxy_servers:
  - server1.mydomain.com
  - server2.mydomain.com
  - server3.mydomain.com

The following is the task/haproxy-apt.yml file that is used to install haproxy on Ubuntu. If you are using CentOS or RedHat you can use ‘yum’ instead of ‘apt’

---
# TASK: Install and configure HAProxy - Ubuntu style
#

- name: Install HAProxy
  action: apt pkg=$item state=latest
  with_items:
    - haproxy
  
- name: Enable HAProxy service
  action: service name=haproxy enabled=yes
  
- name: Copy Ubuntu default file
  action: >
    copy dest=/etc/default/haproxy
    src=../packages/files/haproxy/default
    owner=root group=root mode=0444
  notify: restart haproxy
  # Note the notify clause is handled by a
  # Ansible handler (explained below)

The content for rsyslog.conf, haproxy.logrotate and 49-haproxy.conf can be found in the previous blog entry

However, this time we are templating haproxy.cfg with jinja2 and the content is:

global
	log 127.0.0.1	local0
	log 127.0.0.1	local1 notice
	maxconn 4096
	user haproxy
	group haproxy
	daemon

defaults
	log	global
	mode	http
	option	httplog
	option	dontlognull
	retries	3
	option redispatch
	maxconn	2000
	contimeout	5000
	clitimeout	50000
	srvtimeout	50000

	stats enable
	stats auth		admin:password
	stats uri		/monitor
	stats refresh	5s
	option httpchk	GET /status
	retries		5
	option redispatch
	errorfile	503	/etc/haproxy/errors/503.http
	errorfile	400	/etc/haproxy/errors/400.http
	errorfile	403	/etc/haproxy/errors/403.http
	errorfile	408	/etc/haproxy/errors/408.http
	errorfile	500	/etc/haproxy/errors/500.http
	errorfile	502	/etc/haproxy/errors/502.http
	errorfile	503	/etc/haproxy/errors/503.http
	errorfile	504	/etc/haproxy/errors/504.http
	balance roundrobin	# each server is used in turns, according to assigned weight

listen http-in
	bind :80
	monitor-uri   /haproxy  # end point to monitor HAProxy status (returns 200)
	# option httpclose
	{% for dmp_server in dmp_servers %}
	server {{ dmp_server }} {{ dmp_server }}:{{ dmp_port }} weight 1 maxconn 1000 check inter 4000
	{% endfor %}
	rspidel ^Set-cookie:\ IP=	# do not let this cookie tell our internal IP address

Include handlers at the end of the file:

  handlers:
    - include: handlers/main.yml

The content of handlers/main.yml looks like this:

---
# Ansible Handlers

- name: restart haproxy
  action: service name=haproxy state=restarted
  
- name: restart rsyslog
  action: service name=rsyslog state=restarted

Optional

Include Scout (https://scoutapp.com) and Papertrail (https://papertrailapp.com) More on this later…

    # Scout
    - include: tasks/scout.yml
      when: env == 'prod'

    # Papertrail for logging
    - include: tasks/papertrail.yml
      when: env == 'prod'

Now run it:

ansible-playbook -T 120 -i <inventory-file> haproxy.yml