emq2.3.X会出现这个错误，怎么破？出现这个错误，emq程序无法正常启动，1883端口没有在监听。
emqttd broker is starting...[ok]
emqttd alarm is starting...[ok]
emqttd mod supervisor is starting...[ok]
emqttd bridge supervisor is starting...[ok]
emqttd access control is starting...[ok]
emqttd system monitor is starting...[ok]
emqttd 2.3.6 is running now
Eshell V9.3 (abort with ^G)
(emq@127.0.0.1)1> 13:27:04.684 [error] Autocluster exception: {badmatch,undefined}
主要原因是emqttd_plugins.erl文件的
plugin(CfgFile) ->
{ok, Attrs} = application:get_all_key(AppName),
得不到正确的key导致的。
(emq@192.168.83.128)1> filelib:wildcard("*.{conf,config}", "etc/plugins/").
["emq_auth_clientid.conf","emq_auth_http.conf",
"emq_auth_jwt.conf","emq_auth_ldap.conf",
"emq_auth_mongo.conf","emq_auth_mysql.conf",
"emq_auth_pgsql.conf","emq_auth_redis.conf",
"emq_auth_username.conf","emq_coap.conf",
"emq_dashboard.conf","emq_lua_hook.conf","emq_modules.conf",
"emq_plugin_kafka_brod.config","emq_plugin_template.config",
"emq_recon.conf","emq_reloader.conf","emq_retainer.conf",
"emq_sn.conf","emq_stomp.conf","emq_web_hook.conf",
"firecat_api.conf","firecat_api.config",
"firecat_info.config"]
(emq@192.168.83.128)2> application:get_all_key(firecat_info).
{ok,[{description,"emqttd info save to MySQL"},
{id,[]},
{vsn,"1.1.2"},
{modules,[firecat_info_app,firecat_info_data,
firecat_info_data_sup,firecat_info_mysql,
firecat_info_mysql_sup]},
{maxP,infinity},
{maxT,infinity},
{registered,[]},
{included_applications,[]},
{applications,[stdlib,kernel,ecpool,mysql]},
{env,[{included_applications,[]}]},
{mod,{firecat_info_app,[]}},
{start_phases,undefined}]}
如果有问题会显示undefined.
我的解决方法是：把deps文件夹自己写的插件删掉，再重新拷贝一份进来。/home/emqx-rel-2.3.11/data/loaded_plugins设置自启动插件，里面没有的内容，deps文件夹就不要有相应的插件源码存在（仅针对自己写的插件）。
