执行

rs.addArb("ip:port")

添加仲裁节点一直无响应，很长时间后返回错误信息

“errmsg” : “Reconfig attempted to install a config that would change the implicit default write concern. Use the setDefaultRWConcern command to set a cluster-wide write concern and try the reconfig again.”

解决办法 在 主节点 设置

db.adminCommand({
  "setDefaultRWConcern" : 1,
  "defaultWriteConcern" : {
    "w" : 2
  }
})