diff --git a/spec/helpers/acceptance/tests/hiera_shared_examples.rb b/spec/helpers/acceptance/tests/hiera_shared_examples.rb
index 93d9434..b06dfe9 100644
--- a/spec/helpers/acceptance/tests/hiera_shared_examples.rb
+++ b/spec/helpers/acceptance/tests/hiera_shared_examples.rb
@@ -1,89 +1,91 @@
 # frozen_string_literal: true
 
 require 'tempfile'
 require 'helpers/acceptance/tests/basic_shared_examples'
 require 'helpers/acceptance/tests/plugin_shared_examples'
 
 agents = only_host_with_role(hosts, 'agent')
 
 shared_examples 'hiera tests with' do |es_config, additional_yaml = {}|
   hieradata = {
     'elasticsearch::config' => es_config
   }.merge(additional_yaml).to_yaml
 
   before :all do # rubocop:disable RSpec/BeforeAfterAll
     write_hieradata_to(agents, hieradata)
   end
 
   include_examples('basic acceptance tests', es_config)
 end
 
 shared_examples 'hiera acceptance tests' do |es_config, plugins|
   describe 'hiera', :then_purge do
     let(:manifest) do
       package = if v[:is_snapshot]
                   <<-MANIFEST
                     manage_repo => false,
                     package_url => '#{v[:snapshot_package]}',
                   MANIFEST
                 else
                   <<-MANIFEST
                     # Hard version set here due to plugin incompatibilities.
                     version => '#{v[:elasticsearch_full_version]}',
                   MANIFEST
                 end
 
       <<-MANIFEST
         api_timeout => 60,
         jvm_options => [
           '-Xms128m',
           '-Xmx128m',
         ],
         oss => #{v[:oss]},
         #{package}
       MANIFEST
     end
 
     let(:manifest_class_parameters) { 'restart_on_change => true' }
 
     after :all do # rubocop:disable RSpec/BeforeAfterAll
       write_hieradata_to(agents, {})
 
       # Ensure that elasticsearch is cleaned up before any other tests
       cleanup_manifest = <<-EOS
         class { 'elasticsearch': ensure => 'absent', oss => #{v[:oss]} }
       EOS
       apply_manifest(cleanup_manifest, debug: v[:puppet_debug])
     end
 
     describe 'with hieradata' do
-      nodename = SecureRandom.hex(10)
+      # Remove leading 0: 01234567 is valid octal, but 89abcdef is not and the
+      # serialisation will cause trouble for the test suite (quoting the value?).
+      nodename = SecureRandom.hex(10).sub(%r{^0+}, '')
       include_examples(
         'hiera tests with',
         es_config.merge('node.name' => nodename)
       )
     end
 
     plugins.each_pair do |plugin, _meta|
       describe "with plugin #{plugin}" do
         nodename = SecureRandom.hex(10)
         include_examples(
           'hiera tests with',
           es_config.merge('node.name' => nodename),
           'elasticsearch::plugins' => {
             plugin => {
               'ensure' => 'present'
             }
           }
         )
 
         include_examples(
           'plugin API response',
           es_config.merge('node.name' => nodename),
           'reports the plugin as installed',
           'name' => plugin
         )
       end
     end
   end
 end