diff --git a/lib/vmpooler.rb b/lib/vmpooler.rb
index 4712153..af51436 100644
--- a/lib/vmpooler.rb
+++ b/lib/vmpooler.rb
@@ -83,7 +83,11 @@ module Vmpooler
     parsed_config[:config]['experimental_features']              = ENV['EXPERIMENTAL_FEATURES'] if ENV['EXPERIMENTAL_FEATURES']
     parsed_config[:config]['purge_unconfigured_resources']       = ENV['PURGE_UNCONFIGURED_RESOURCES'] if ENV['PURGE_UNCONFIGURED_RESOURCES']
     # ENV PURGE_UNCONFIGURED_FOLDERS deprecated, will be removed in version 3
-    parsed_config[:config]['purge_unconfigured_resources']       = ENV['PURGE_UNCONFIGURED_FOLDERS'] if ENV['PURGE_UNCONFIGURED_FOLDERS']
+    if ENV['PURGE_UNCONFIGURED_FOLDERS']
+      puts '[!] [deprecation] rename ENV var \'PURGE_UNCONFIGURED_FOLDERS\' to \'PURGE_UNCONFIGURED_RESOURCES\''
+      # backwards compatibility
+      parsed_config[:config]['purge_unconfigured_resources']     = ENV['PURGE_UNCONFIGURED_FOLDERS']
+    end
     parsed_config[:config]['usage_stats']                        = ENV['USAGE_STATS'] if ENV['USAGE_STATS']
     parsed_config[:config]['request_logger']                     = ENV['REQUEST_LOGGER'] if ENV['REQUEST_LOGGER']
     parsed_config[:config]['create_template_delta_disks']        = ENV['CREATE_TEMPLATE_DELTA_DISKS'] if ENV['CREATE_TEMPLATE_DELTA_DISKS']
diff --git a/lib/vmpooler/providers/base.rb b/lib/vmpooler/providers/base.rb
index c647708..1468cf8 100644
--- a/lib/vmpooler/providers/base.rb
+++ b/lib/vmpooler/providers/base.rb
@@ -237,7 +237,7 @@ module Vmpooler
           raise("#{self.class.name} does not implement get_target_datacenter_from_config")
         end
 
-        def purge_unconfigured_resources(_whitelist)
+        def purge_unconfigured_resources(_allowlist)
           raise("#{self.class.name} does not implement purge_unconfigured_resources")
         end