Table of Contents

1. Overview
2. Install Varnish
3. Class varnish
4. Class varnish::vcl
   • varnish::vcl::selector
   • Configure VCL with class varnish::vcl
5. Tests
6. Contributing
7. Contributors

Overview

This Puppet module installs and configures Varnish. It also allows to manage Varnish VCL. Tested on Ubuntu, CentOS, RHEL and Oracle Linux.

The Module is based on https://github.com/maxchk/puppet-varnish Since than to release 3.0.0

• Added support for new OS
• Dropped support outdated OS
• Moved VCL Subclasses (acl, acl_member, backend, director, probe, selector)
• Added support for varnish 6
• Added support for varnish-plus / Varnish Enterprise

Detailed Reference to all classparameters can be found in (https://github.com/voxpupuli/puppet-varnish/blob/master/REFERENCE.md)

Important information

Version 2.0.0 drops support for old OS Versions (pre systemd) Also drops support for pre Varnish 4

Install Varnish

installs Varnish allocates for cache 1GB (malloc) starts it on port 80:

class {'varnish':
  varnish_listen_port => 80,
  varnish_storage_size => '1G',
}

Class varnish

Class varnish Installs Varnish. Provides access to all configuration parameters. Controls Varnish service. By default mounts shared memory log directory as tmpfs.

All parameters are low case replica of actual parameters passed to the Varnish conf file, $class_parameter -> VARNISH_PARAMETER, i.e.

$memlock             -> MEMLOCK
$varnish_vcl_conf    -> VARNISH_VCL_CONF
$varnish_listen_port -> VARNISH_LISTEN_PORT

Exceptions are: shmlog_dir - location for shmlog shmlog_tempfs - mounts shmlog directory as tmpfs, (default value: true) version - passes to puppet type 'package', attribute 'ensure', (default value: present)

At minimum you may want to change a value for default port: varnish_listen_port => '80'

For more details on parameters, check class varnish.

Class varnish vcl

Class varnish::vcl manages Varnish VCL configuration.

Varnish VCL applies following restictions: if you define an acl it must be used if you define a probe it must be used if you define a backend it must be used if you define a director it must be used

Gives access to Varnish acl, probe, backend, director, etc. definitions (see below)

varnish selector

Definition varnish::vcl::selector allows to configure Varnish selector.

While acl, probe, backend and director are self-explanatory WTF is selector?

You cannot define 2 or more backends/directors and not to use them. This will result in VCL compilation failure.

Parameter selectors gives access to req.backend inside vcl_recv. Code:

varnish::vcl::selector { 'cluster1': condition => 'req.url ~ "^/cluster1"' }
varnish::vcl::selector { 'cluster2': condition => 'true' } # will act as backend set by else statement

Will result in following VCL configuration to be generated:

if (req.url ~ "^/cluster1") {
  set req.backend = cluster1;
}
if (true) {
  set req.backend = cluster2;
}

For more examples see tests/vcl_backends_probes_directors.pp

Usaging class varnish::vcl

Configure probes, backends, directors and selectors

  class { 'varnish::vcl': }

configure probes

varnish::probe { 'health_check1': url => '/health_check_url1' }
varnish::probe { 'health_check2':
  window    => '8',
  timeout   => '5s',
  threshold => '3',
  interval  => '5s',
  request   => [ "GET /healthCheck2 HTTP/1.1", "Host: www.example1.com", "Connection: close" ]
}

configure backends

varnish::vcl::backend { 'srv1': host => '172.16.0.1', port => '80', probe => 'health_check1' }
varnish::vcl::backend { 'srv2': host => '172.16.0.2', port => '80', probe => 'health_check1' }
varnish::vcl::backend { 'srv3': host => '172.16.0.3', port => '80', probe => 'health_check2' }
varnish::vcl::backend { 'srv4': host => '172.16.0.4', port => '80', probe => 'health_check2' }
varnish::vcl::backend { 'srv5': host => '172.16.0.5', port => '80', probe => 'health_check2' }
varnish::vcl::backend { 'srv6': host => '172.16.0.6', port => '80', probe => 'health_check2' }

configure directors

varnish::vcl::director { 'cluster1': backends => [ 'srv1', 'srv2' ] }
varnish::vcl::director { 'cluster2': backends => [ 'srv3', 'srv4', 'srv5', 'srv6' ] }

configure selectors

  varnish::vcl::selector { 'cluster1': condition => 'req.url ~ "^/cluster1"' }
  varnish::vcl::selector { 'cluster2': condition => 'true' } # will act as backend set by else statement

If modification to Varnish VCL goes further than configuring probes, backends and directors parameter template can be used to point varnish::vcl class at a different template.

NOTE: If you copy existing template and modify it you will still be able to use probes, backends, directors and selectors.

Redefine functions in class varnish::vcl

With the module comes the basic Varnish vcl configuration file. If needed one can replace default functions in the configuration file with own ones and/or define custom functions. Override or custom functions specified in the array passed to varnish::vcl class as parameter functions. The best way to do it is to use hiera. For example:

varnish::vcl::functions:
  vcl_hash: |
    hash_data(req.url);
    if (req.http.host) {
      hash_data(req.http.host);
    } else {
      hash_data(server.ip);
    }
    return (hash);
  pipe_if_local: |
    if (client.ip ~ localnetwork) {
      return (pipe);
    }

There are two special cases for functions vcl_init and vcl_recv. For Varnish version 4 in function vcl_init include directive for directors is always present. For function vcl_recv beside the possibility to override standard function one can also add peace of code to the begining or to the end of the function with special names vcl_recv_prepend and vcl_recv_append For instance:

varnish::vcl::functions:
  pipe_if_local: |
    if (client.ip ~ localnetwork) {
      return (pipe);
    }
  vcl_recv_prepend: |
    call pipe_if_local;

Tests

For more examples check module tests directory. NOTE: make sure you don't run tests on Production server.

Contributing

Please report bugs and feature request using GitHub issue tracker.

For pull requests, it is very much appreciated to check your Puppet manifest with puppet-lint to follow the recommended Puppet style guidelines from the Puppet Labs style guide.

Contributors

• Max Horlanchuk [email protected]
• Fabio Rauber [email protected]
• Samuel Leathers [email protected]
• Lienhart Woitok [email protected]
• Adrian Webb [email protected]
• Frode Egeland [email protected]
• Matt Ward [email protected]
• Noel Sharpe [email protected]
• Rich Kang [email protected]
• browarrek [email protected]
• Stanislav Voroniy [email protected]
• Hannes Schaller [email protected]
• Lukas Plattner [email protected]