有些时候有于硬件资源有限，所以我们不得不进行一些回收工作，下面我们就要将刚刚启用的Shard Server 回收，系统首先会将在这个即将被移除的Shard Server 上的数据先平均分配到其它的Shard Server 上，然后最终在将这个Shard Server 踢下线,我们需要不停的调用db.runcommand({"removeshard" :"localhost:20002"});来观察这个移除操作进行到哪里了：
- >useadmin
- switchedtodbadmin
- >db.runcommand({"removeshard":"localhost:20002"});
- {
- "msg":"drainingstartedsuccessfully",
- "state":"started",
- "shard":"shard0002",248); line-height:21px; margin:0px!important; padding:0px 3px 0px 10px!important"> "ok":1
- }
- >db.runcommand({"removeshard":"localhost:20002"});
- {
- "msg":"drainingongoing",108); List-style:decimal-leading-zero outsIDe; color:inherit; line-height:21px; margin:0px!important; padding:0px 3px 0px 10px!important"> "state":"ongoing",248); line-height:21px; margin:0px!important; padding:0px 3px 0px 10px!important"> "remaining":{
- "chunks":numberLong(44),248); line-height:21px; margin:0px!important; padding:0px 3px 0px 10px!important"> "dbs":numberLong(0)
- },248); line-height:21px; margin:0px!important; padding:0px 3px 0px 10px!important"> ……
- "msg":"drainingongoing",248); line-height:21px; margin:0px!important; padding:0px 3px 0px 10px!important"> "state":"ongoing",108); List-style:decimal-leading-zero outsIDe; color:inherit; line-height:21px; margin:0px!important; padding:0px 3px 0px 10px!important"> "remaining":{
- "chunks":numberLong(1),108); List-style:decimal-leading-zero outsIDe; color:inherit; line-height:21px; margin:0px!important; padding:0px 3px 0px 10px!important"> "dbs":numberLong(0)
- },108); List-style:decimal-leading-zero outsIDe; color:inherit; line-height:21px; margin:0px!important; padding:0px 3px 0px 10px!important"> "ok":1
- }
- "msg":"removeshardcompletedsuccessfully",248); line-height:21px; margin:0px!important; padding:0px 3px 0px 10px!important"> "state":"completed",248); line-height:21px; margin:0px!important; padding:0px 3px 0px 10px!important"> "assertion":"can'tfindshardfor:localhost:20002",108); List-style:decimal-leading-zero outsIDe; color:inherit; line-height:21px; margin:0px!important; padding:0px 3px 0px 10px!important"> "assertionCode":13129,248); line-height:21px; margin:0px!important; padding:0px 3px 0px 10px!important"> "errmsg":"dbassertionfailure",108); List-style:decimal-leading-zero outsIDe; color:inherit; line-height:21px; margin:0px!important; padding:0px 3px 0px 10px!important"> "ok":0
- }
最终移除后，当我们再次调用db.runcommand(
{"removeshard" : "localhost:20002"}
);的时候
系统会报错，已
便通知我们不存在20002 这个端口的Shard Server 了，因为它已经被移除掉了。
