diff --git a/lib/dcell/node.rb b/lib/dcell/node.rb
index 7344bd2..48434e3 100644
--- a/lib/dcell/node.rb
+++ b/lib/dcell/node.rb
@@ -134,6 +134,7 @@ def shutdown
       NodeCache.delete @id
       MailboxManager.delete Thread.mailbox
       Logger.info "Disconnected from #{@id}"
+      instance_variables.each { |iv| remove_instance_variable iv }
     end
 
     # Obtain socket for relay messages
diff --git a/lib/dcell/server.rb b/lib/dcell/server.rb
index c2e5024..c5597f3 100644
--- a/lib/dcell/server.rb
+++ b/lib/dcell/server.rb
@@ -61,6 +61,7 @@ def shutdown
         @socket.write msg
       end
       @socket.close
+      instance_variables.each { |iv| remove_instance_variable iv }
     end
 
     def write(id, msg)