anchor.diff:  -define(NS_LOG, "ns_log").
   
   get_current_version() ->
  -    {3,0,0}.
  +    {2,3,0}.
   
   % Allow all keys to be mergable.
   
  
positive.code:     do_upgrade_files_from_2_0_to_2_2_0(DataDir),
      do_upgrade_config_from_2_0_to_2_2_0(Config, DefaultConfig, DataDir).
  
  upgrade_config_from_2_2_0_to_3_0(Config) ->
      ?log_info("Upgrading config from 2.2.0 to 3.0"),
      {value, MemcachedConfig} = ns_config:search(Config, {node, node(), memcached}),
      MemcachedConfig1 = lists:keystore(log_generations, 1, MemcachedConfig,
                                        {log_generations, 20}),
  
negative.code:        {dedicated_port, misc:get_env_default(memcached_dedicated_port, 11209)},
         {admin_user, "_admin"},
         %% Note that this is not actually the password that is being used; as
         %% part of upgrading config from 2.2 to 2.3 version it's replaced by
         %% unique per-node password. I didn't put it here because default()
         %% supposed to be a pure function.
         {admin_pass, ""},
  