diff --git a/lib/facter/rh_certificates.rb b/lib/facter/rh_certificates.rb
index 743ff78..96c78c8 100644
--- a/lib/facter/rh_certificates.rb
+++ b/lib/facter/rh_certificates.rb
@@ -1,4 +1,5 @@
 Facter.add('rh_certificate') do
+  confine kernel: 'Linux'
   setcode do
     data = Facter::Util::Resolution.exec('/usr/sbin/subscription-manager config')
     break if data.nil? || data.empty?