mongodb replication

Official documentation: https://docs.mongodb.com/manual/replication/

Start parameters:

The mongodb installed through the Linux package manager (for example: yum) will generate a default configuration file: /etc/mongod.conf,

When installing from source, you need to specify a configuration file yourself.

One is the command line parametersmongod --replSet="setname"

The other is to add in the configuration filereplication.replSetName="setname"

After starting all mongodb instances, log in to one of them to set up:

Related official documents: https://docs.mongodb.com/manual/reference/method/js-replication/

s = { 
  _id: <string>, 
  members: [ 
    { 
      _id: <int>, 
      host: <string>, 
　　　 arbiterOnly: <boolean>, 
      priority: <number> 
    }, 
    ... 
  ], 
} 
rs.initiate (s) Initialize or call rs.reconfig (s) to reset. 
Check the configuration through rs.conf ()