diff --git a/lib/refrepo/gen/puppet/oarsub-simplifier-aliases.rb b/lib/refrepo/gen/puppet/oarsub-simplifier-aliases.rb
index 52498e3720727cd98c0490390438bd1de71e3684..29a6d27be0612a2e71ebbecb6a20324cfd7caadb 100644
--- a/lib/refrepo/gen/puppet/oarsub-simplifier-aliases.rb
+++ b/lib/refrepo/gen/puppet/oarsub-simplifier-aliases.rb
@@ -61,11 +61,10 @@ def generate_all_sites_aliases
       aliases[site][cluster] = "cluster='#{cluster}'"
       aliases[site]["#{cluster}-%d"] = "host='#{cluster}-%d.#{site}.grid5000.fr'"
     end
-    aliases[site] = aliases[site].sort_by { |site_name, _| site_name }.to_h
+    aliases[site] = aliases[site].sort_by { |cluster, _| [cluster[/(\D+)/, 1], cluster[/(\d+)/, 1].to_i] }.to_h
   end
 
   aliases = aliases.sort_by { |site, _| site }.to_h
-
   aliases
 end