diff --git a/manifests/init.pp b/manifests/init.pp
index f4c48df..6965729 100644
--- a/manifests/init.pp
+++ b/manifests/init.pp
@@ -1,121 +1,121 @@
 # == Class: varnish
 #
 # Configure Varnish proxy cache
 #
 # === Parameters
 #
 # [*addrepo*]
 #   Whether to add the official Varnish repos
 # [*secret*]
 #   Varnish secret (used by varnishadm etc).
 #   Optional; will be autogenerated if not specified
 # [*vcl_conf*]
 #   Location of Varnish config file template
 # [*listen*]
 #   IP address for HTTP to listen on
 # [*listen_port*]
 #   Port to listen on for HTTP requests
 # [*admin_listen*]
 #   IP address for admin requests - defaults to 127.0.0.1
 # [*admin_port*]
 #   Port for Varnish admin to listen on
 # [*min_threads*]
 #   Varnish minimum thread pool size
 # [*max_threads*]
 #   Varnish maximum thread pool size
 # [*thread_timeout*]
 #   Thread timeout
 # [*storage_type*]
 #   Whether to use malloc (RAM only) or file storage for cache
 # [*storage_size*]
 #   Size of cache
 # [*varnish_version*]
 #   Major Varnish version to use
 # [*vcl_reload*]
 #   Script to use to load new Varnish config
 # [*package_ensure*]
 #   Ensure specific package version for Varnish, eg 3.0.5-1.el6
 # [*runtime_params*]
 #   Hash of key:value runtime parameters
 #
 class varnish (
   $runtime_params  = {},
   $addrepo         = true,
   $admin_listen    = '127.0.0.1',
   $admin_port      = '6082',
   $listen          = '0.0.0.0',
   $listen_port     = '6081',
   $secret          = undef,
   $secret_file     = '/etc/varnish/secret',
   $vcl_conf        = '/etc/varnish/default.vcl',
   $storage_type    = 'file',
   $storage_file    = '/var/lib/varnish/varnish_storage.bin',
   $storage_size    = '1G',
   $min_threads     = '50',
   $max_threads     = '1000',
   $thread_timeout  = '120',
   $varnish_version = '4.1',
+  $instance_name   = undef,
   $package_ensure  = 'present',
   $package_name    = 'varnish',
   $service_name    = 'varnish',
   $vcl_reload_cmd  = undef,
   $vcl_reload_path = $::path,
 ) {
 
   if $package_ensure == 'present' {
     $version_major = regsubst($varnish_version, '^(\d+)\.(\d+).*$', '\1')
     $version_minor = regsubst($varnish_version, '^(\d+)\.(\d+).*$', '\2')
     $version_full  = $varnish_version
   } else {
     $version_major = regsubst($package_ensure, '^(\d+)\.(\d+).*$', '\1')
     $version_minor = regsubst($package_ensure, '^(\d+)\.(\d+).*$', '\2')
     $version_full = "${version_major}.${version_minor}"
     if $varnish_version != "${version_major}.${version_minor}" {
       fail("Version mismatch, varnish_version is ${varnish_version}, but package_ensure is ${version_full}")
     }
   }
 
   include ::varnish::params
 
   if $vcl_reload_cmd == undef {
     $vcl_reload = $::varnish::params::vcl_reload
   } else {
     $vcl_relaod = $vcl_reload_cmd
   }
 
   validate_bool($addrepo)
   validate_string($secret)
   validate_absolute_path($secret_file)
-  unless is_integer($listen_port) { fail('listen_port invalid') }
   unless is_integer($admin_port) { fail('admin_port invalid') }
   unless is_integer($min_threads) { fail('min_threads invalid') }
   unless is_integer($max_threads) { fail('max_threads invalid') }
   validate_absolute_path($storage_file)
   validate_hash($runtime_params)
   validate_re($storage_type, '^(malloc|file)$')
   validate_re("${version_major}.${version_minor}", '^[3-5]\.[0-9]')
 
   if $addrepo {
     class { '::varnish::repo':
       before => Class['::varnish::install'],
     }
   }
 
   include ::varnish::install
 
 
   class { '::varnish::secret':
     secret  => $secret,
     require => Class['::varnish::install'],
   }
 
   class { '::varnish::config':
     require => Class['::varnish::secret'],
     notify  => Class['::varnish::service'],
   }
 
   class { '::varnish::service':
     require => Class['::varnish::config'],
   }
 
 }
diff --git a/templates/sysconfig.erb b/templates/sysconfig.erb
index f7cb145..fbfacd8 100644
--- a/templates/sysconfig.erb
+++ b/templates/sysconfig.erb
@@ -1,39 +1,42 @@
 ############################################
 # WARNING:
 # Managed by Puppet - DO NOT modify locally!
 ############################################
 
 START=yes
 NFILES=131072
 MEMLOCK=82000
 
 RELOAD_VCL=1
 VARNISH_VCL_CONF=<%= scope['::varnish::vcl_conf'] %>
 VARNISH_LISTEN_ADDRESS=<%= scope['::varnish::listen'] %>
 VARNISH_LISTEN_PORT=<%= scope['::varnish::listen_port'] %>
 VARNISH_ADMIN_LISTEN_ADDRESS=<%= scope['::varnish::admin_listen'] %>
 VARNISH_ADMIN_LISTEN_PORT=<%= scope['::varnish::admin_port'] %>
 VARNISH_SECRET_FILE=<%= scope['::varnish::secret_file'] %>
 VARNISH_MIN_THREADS=<%= scope['::varnish::min_threads'] %>
 VARNISH_MAX_THREADS=<%= scope['::varnish::max_threads'] %>
 VARNISH_THREAD_TIMEOUT=<%= scope['::varnish::thread_timeout'] %>
 VARNISH_STORAGE=<%= scope['::varnish::storage_type'] %>,<% if scope['::varnish::storage_type'] == 'file' -%><%= scope['::varnish::storage_file'] %>,<% end -%><%= scope['::varnish::storage_size'] %>
 VARNISH_TTL=120
 
 DAEMON_OPTS="<% if scope['::varnish::params::service_provider'] == 'sysvinit' -%><%= scope['::varnish::config::jail_opt'] %> \<% end %>
              -a ${VARNISH_LISTEN_ADDRESS}:${VARNISH_LISTEN_PORT} \
+<% if scope['::varnish::instance_name'] != :undefined -%>
+             -n <%= scope['::varnish::instance_name'] %> \
+<% end -%>
              -f ${VARNISH_VCL_CONF} \
              -T ${VARNISH_ADMIN_LISTEN_ADDRESS}:${VARNISH_ADMIN_LISTEN_PORT} \
              -t ${VARNISH_TTL} \
 <% if scope['::varnish::version_major'] == '3' -%>
              -w ${VARNISH_MIN_THREADS},${VARNISH_MAX_THREADS},${VARNISH_THREAD_TIMEOUT} \
 <% else -%>
              -p thread_pool_min=${VARNISH_MIN_THREADS} \
              -p thread_pool_max=${VARNISH_MAX_THREADS} \
              -p thread_pool_timeout=${VARNISH_THREAD_TIMEOUT} \
 <% end -%>
 <% scope['::varnish::runtime_params'].each do |k,v| -%>
              -p <%= k %>=<%= v %> \
 <% end -%>
              -S ${VARNISH_SECRET_FILE} \
              -s ${VARNISH_STORAGE}"
diff --git a/templates/varnish.service.erb b/templates/varnish.service.erb
index 97c0d52..980d8d3 100644
--- a/templates/varnish.service.erb
+++ b/templates/varnish.service.erb
@@ -1,32 +1,35 @@
 [Unit]
 Description=Varnish HTTP accelerator
 
 [Service]
 Type=forking
 LimitNOFILE=131072
 LimitMEMLOCK=82000
 LimitCORE=infinity
 PrivateTmp=true
 
 ExecReload=<%= scope['::varnish::vcl_reload'] %>
 ExecStart=/usr/sbin/varnishd <%= scope['::varnish::config::jail_opt'] %> \
   -P /var/run/varnish.pid \
   -t 120 \
+<% if scope['::varnish::instance_name'] != :undefined -%>
+  -n <%= scope['::varnish::instance_name'] %> \
+<% end -%>
   -f <%= scope['::varnish::vcl_conf'] %> \
   -a <%= scope['::varnish::listen'] %>:<%= scope['::varnish::listen_port'] %> \
   -T <%= scope['::varnish::admin_listen'] %>:<%= scope['::varnish::admin_port'] %> \
 <% if scope['::varnish::version_major'] == '3' -%>
   -w <%= scope['::varnish::min_threads'] %>,<%= scope['::varnish::max_threads'] %>,<%= scope['::varnish::thread_timeout'] %> \
 <% else -%>
   -p thread_pool_min=<%= scope['::varnish::min_threads'] %> \
   -p thread_pool_max=<%= scope['::varnish::max_threads'] %> \
   -p thread_pool_timeout=<%= scope['::varnish::thread_timeout'] %> \
 <% end -%>
 <% scope['::varnish::runtime_params'].each do |k,v| -%>
   -p <%= k %>=<%= v %> \
 <% end -%>
   -S <%= scope['::varnish::secret_file'] %> \
   -s <%= scope['::varnish::storage_type'] %>,<% if scope['::varnish::storage_type'] == 'file' -%><%= scope['::varnish::storage_file'] %>,<% end -%><%= scope['::varnish::storage_size'] %>
 
 [Install]
 WantedBy=multi-user.target