diff --git a/manifests/module/ippool.pp b/manifests/module/ippool.pp
index 6dc9ad66..79680b43 100644
--- a/manifests/module/ippool.pp
+++ b/manifests/module/ippool.pp
@@ -12,6 +12,13 @@
   Integer $maximum_timeout      = 0,
   Optional[String] $key         = undef,
 ) {
+  if ($cache_size !~ Undef) {
+    $real_cache_size = $cache_size
+  } else {
+    $real_cache_size = inline_template(@("IPADDRRANGE"/L))
+      <%- require 'ipaddr' -%><%=(IPAddr.new @range_stop).to_i - (IPAddr.new @range_start).to_i + 1 %>
+    |-IPADDRRANGE
+  }
 
   freeradius::module { "ippool_${name}":
     ensure  => $ensure,
diff --git a/spec/defines/module/ippool_spec.rb b/spec/defines/module/ippool_spec.rb
new file mode 100644
index 00000000..1ab3ec20
--- /dev/null
+++ b/spec/defines/module/ippool_spec.rb
@@ -0,0 +1,23 @@
+require 'spec_helper'
+
+describe 'freeradius::module::ippool' do
+  include_context 'redhat_common_dependencies'
+
+  let(:title) { 'test' }
+
+  let(:params) do
+    {
+      range_start: '192.168.0.1',
+      range_stop: '192.168.0.10',
+      netmask: '255.255.255.0',
+    }
+  end
+
+  it do
+    is_expected.to contain_freeradius__module('ippool_test')
+      .with_content(%r{^\s+range_start = 192.168.0.1$})
+      .with_content(%r{^\s+range_stop = 192.168.0.10$})
+      .with_content(%r{^\s+netmask = 255.255.255.0$})
+      .with_content(%r{^\s+cache_size = 10$})
+  end
+end
diff --git a/templates/ippool.erb b/templates/ippool.erb
index 8abb8dec..32555594 100644
--- a/templates/ippool.erb
+++ b/templates/ippool.erb
@@ -1,5 +1,3 @@
-<%- require 'ipaddr' -%>
-
 #  Do server side ip pool management. Should be added in
 #  post-auth and accounting sections.
 #
@@ -37,11 +35,7 @@ ippool <%= @name %> {
   #  The gdbm cache size for the db files. Should
   #  be equal to the number of ip's available in
   #  the ip pool
-<%- if @cache_size -%>
-  cache_size = <%= @cache_size %>
-<%- else -%>
-  cache_size = <%= (IPAddr.new @range_stop).to_i() - (IPAddr.new @range_start).to_i() + 1 %>
-<%- end -%>
+  cache_size = <%= @real_cache_size %>
 
   #  Helper db index file used in multilink
 <%- if @ip_index -%>