hub: 
  clientid: Client ID of Client connection Hub. It should not be empty when cleansession is false. 
  address: [Must] Address of Client connection Hub. 
  username: [Must] User name of Client connection Hub. 
  password:If you use account password, you must fill out the password of Client connection Hub, outherwise you do not need to fill out it. 
  ca: If certificate two-way authentication is adopted, the CA certificate path of Client connection Hub should be filled out. 
  key: If certificate two-way authentication is adopted, the client private key path of Client connection Hub should be filled out. 
  cert: If certificate two-way authentication is adopted, the client public key path of Client connection Hub should be filled out. 
  timeout: Default value: 30s, Time-out period of Client connection Hub 
  interval: Default value: 1m, Maximum interval time for reconnection of Client connection Hub, increasing to the maximum value from 500 microseconds by doubling. 
  keepalive: Default value: 1m, Holding time of Client connection Hub 
  cleansession:Default value: false, Session persistence of Client connection Hub or not. 
  validatesubs: Default value: false, Client checks Hub subscription result or not; exit after reporting of error in case of subscription failure discovered. 
  buffersize: Default value: 10, Size of memory queue for Client to send messages to Hub; message loss can be caused by abnormal exit, and the messages with QoS = 1 will depend on Hub to resend. 
rules:Routing rule list, subscribing messages from Hub and sending to Remote, or vice versa. 
  - hub: 
      clientid: Client ID of Client connection Hub 
      subscriptions:Message subscribed by Client from Hub, for example 
        - topic: say 
          qos: 1 
        - topic: hi 
          qos: 0 
    remote: 
      name: [Must] Appoint the Remote name, which shall be included in the Remote list. 
      clientid: Client ID of Client connection Remote 
      subscriptions:Message subscribed by Client from Hub, for example 
        - topic: remote/say 
          qos: 0 
        - topic: remote/hi 
          qos: 0 
remotes: Remote list 
  - name: [Must]Remote name, which must be the unique in the list 
    clientid: Client ID of Client connection Remote 
    address: [Must] Address of Client connection Remote 
    username: User name of Client connection Remote 
    password: If you use account password, you must fill out the password of Client connection Hub, otherwise you do not need to fill out it. 
    ca: If certificate two-way authentication is adopted, the CA certificate path of Client connection Remote should be filled out. 
    key: If certificate two-way authentication is adopted, the client private key path of Client connection Remote should be filled out. 
    cert: If certificate two-way authentication is adopted, the client public key path of Client connection Remote should be filled out. 
    timeout: Default value: 30s, Time-out period of Client connection Remote. 
    interval: Default value: 1m, Maximum interval time for reconnection of Client connection Remote, increasing to the maximum value from 500 microseconds by doubling. 
    keepalive: Default value: 1m, Holding time of Client connection Remote. 
    cleansession: Default value: false, Session persistence of Client connection Remote or not. 
    validatesubs: Default value: false, Client checks Remote subscription result or not; exit after reporting of error in case of subscription failure discovered. 
    buffersize: Default value: 10, Size of memory queue for Client to send messages to Remote; message loss can be caused by abnormal exit, and the messages with QoS = 1 should depend on Remote to resend. 
logger: Log configuration item 
  path: It is empty by default, i.e., no file is printed; if a file is appointed, it will be output to file. 
  level: Default value: Info, log level, supporting debug, info, warn and error. 
  format: Default value: Text, log print format, supporting text and json 
  age: 
    max: Default value: 15, Maximum number of days a log file is retained 
  size: 
    max: Default value: 50, Log file size limit, unit MB 
  backup: 
    max: Default value: 15, Maximum number of log files retained