diff --git a/spec/helpers/acceptance/tests/hiera_shared_examples.rb b/spec/helpers/acceptance/tests/hiera_shared_examples.rb
index 93d9434ba..b06dfe998 100644
--- a/spec/helpers/acceptance/tests/hiera_shared_examples.rb
+++ b/spec/helpers/acceptance/tests/hiera_shared_examples.rb
@@ -57,7 +57,9 @@ class { 'elasticsearch': ensure => 'absent', oss => #{v[:oss]} }
     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)