本地用三台机器部署了mongo集群，需要测试能否切换primary和secondary。
于是在关闭primary的时候出现了以下问题：
repset:PRIMARY> use admin
switched to db admin
repset:PRIMARY> db.shutdownServer()
2016-11-14T10:07:51.912+0800 E QUERY [thread1] Error: shutdownServer failed: {
"ok" : 0,
"errmsg" : "shutdown must run from localhost when running db without auth",
"code" : 13
} :
_getErrorWithCode@src/mongo/shell/utils.js:25:13
DB.prototype.shutdownServer@src/mongo/shell/db.js:302:1
@(shell):1:1
解决方法
[grid@mongohost1 mongodb2.6]$ ./bin/mongo --port 33333
MongoDB shell version: 2.6.10
connecting to: 127.0.0.1:33333/test
> use admin
switched to db admin
> db.shutdownServer()
2015-09-09T09:57:30.453+0800 DBClientCursor::init call() failed
server should be down...
2015-09-09T09:57:30.458+0800 trying reconnect to 127.0.0.1:33333 (127.0.0.1) failed
2015-09-09T09:57:30.458+0800 warning: Failed to connect to 127.0.0.1:33333, reason: errno:111 Connection refused
2015-09-09T09:57:30.459+0800 reconnect 127.0.0.1:33333 (127.0.0.1) failed failed couldn't connect to server 127.0.0.1:33333 (127.0.0.1), connection attempt failed
