接下来创建相应数据库并设置其"可以sharding",新建自动切片的库user001：
> config = connect("10.0.4.85:27022")
> config = config.getSisterDB("config")
> dnt_mongodb=db.getSisterDB("dnt_mongodb");
dnt_mongodb
> db.runCommand({enablesharding:"dnt_mongodb"})
{ "ok" : 1 }
> config = config.getSisterDB("config")
> dnt_mongodb=db.getSisterDB("dnt_mongodb");
dnt_mongodb
> db.runCommand({enablesharding:"dnt_mongodb"})
{ "ok" : 1 }
注：一旦enable了个数据库，mongos将会把数据库里的不同数据集放在不同的分片上。除非数据集被分片(下面会设置)，否则一个数据集的所有数据将放在一个分片上。
> db.printShardingStatus();
Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--> --- Sharding Status ---
sharding version: { "_id" : 1, "version" : 3 }
shards:
{ "_id" : "shard0000", "host" : "10.0.4.85:27020" }
{ "_id" : "shard0001", "host" : "10.0.4.85:27021" }
databases:
{ "_id" : "admin", "partitioned" : false, "primary" : "config" }
{ "_id" : "dnt_mongodb", "partitioned" : true, "primary" : "shard0000" }
sharding version: { "_id" : 1, "version" : 3 }
shards:
{ "_id" : "shard0000", "host" : "10.0.4.85:27020" }
{ "_id" : "shard0001", "host" : "10.0.4.85:27021" }
databases:
{ "_id" : "admin", "partitioned" : false, "primary" : "config" }
{ "_id" : "dnt_mongodb", "partitioned" : true, "primary" : "shard0000" }
> db.runCommand( { shardcollection : "dnt_mongodb.posts1", key : {_id : 1}, unique: true } )
{ "collectionsharded" : "dnt_mongodb.posts1", "ok" : 1 }
--使用shardcollection 命令分隔数据集，key自动生成 [必须为唯一索引unique index]。
如果要进行GridFS sharding，则需进行如下设置：
db.runCommand( { shardcollection : "dnt_mongodb.attach_gfstream.chunks", key : { files_id : 1 } } )
{"ok" : 1} ，更多内容参见http://eshilin.blog.163.com/blog/static/13288033020106215227346/
> db.printShardingStatus()
--- Sharding Status ---
sharding version: { "_id" : 1, "version" : 3 }
shards:
{ "_id" : "shard0000", "host" : "localhost:27020" }
{ "_id" : "shard0001", "host" : "localhost:27021" }
databases:
{ "_id" : "admin", "partitioned" : false, "primary" : "config" }
{ "_id" : "user001", "partitioned" : true, "primary" : "shard0000" }
dnt_mongodb.posts1e chunks:
{ "name" : { $minKey : 1 } } -->> { "name" : { $maxKey :
1 } } on : shard0000 { "t" : 1000, "i" : 0
--- Sharding Status ---
sharding version: { "_id" : 1, "version" : 3 }
shards:
{ "_id" : "shard0000", "host" : "localhost:27020" }
{ "_id" : "shard0001", "host" : "localhost:27021" }
databases:
{ "_id" : "admin", "partitioned" : false, "primary" : "config" }
{ "_id" : "user001", "partitioned" : true, "primary" : "shard0000" }
dnt_mongodb.posts1e chunks:
{ "name" : { $minKey : 1 } } -->> { "name" : { $maxKey :
1 } } on : shard0000 { "t" : 1000, "i" : 0
下面我用一个工具来批量向dnt_mongodb数据库的 posts1表中导入数据，大约是16万条数据。导入过程中mongos会显示类似如下信息：
Tue Sep 07 12:13:15 [conn14] autosplitting dnt_mongodb.posts1 size: 47273960 shard: ns:dnt_mongodb.posts1 at: shard0000:10.0.4.85:27020 lastmod: 1|0 min: { _id: MinKey } max: { _id: MaxKey } on: { _id: 19 }(splitThreshold 47185920)
Tue Sep 07 12:13:15 [conn14] config change: { _id: "4_85-2010-09-07T04:13:15-0", server: "4_85", time: new Date(1283832795994), what: "split", ns: "dnt_mongodb.posts1", details: { before: { min: { _id: MinKey }, max: { _id: MaxKey } }, left: { min: { _id: MinKey }, max: { _id: 19 } }, right: { min: { _id: 19 }, max: {_id: MaxKey } } } }
Tue Sep 07 12:13:16 [conn14] moving chunk (auto): ns:dnt_mongodb.posts1 at: shard0000:10.0.4.85:27020 lastmod: 1|1 min: { _id: MinKey } max: { _id: 19 } to: shard0001:10.0.4.85:27021 #objects: 0
Tue Sep 07 12:13:16 [conn14] moving chunk ns: dnt_mongodb.posts1 moving ( ns:dnt_mongodb.posts1 at: shard0000:10.0.4.85:27020 lastmod: 1|1 min: { _id: MinKey }max: { _id: 19 }) shard0000:10.0.4.85:27020 -> shard0001:10.0.4.85:27021
Tue Sep 07 12:13:23 [WriteBackListener] ~ScopedDBConnection: _conn != null
Tue Sep 07 12:13:23 [WriteBackListener] ERROR: splitIfShould failed: ns: dnt_mongodb.posts1 findOne has stale config
Tue Sep 07 12:13:28 [WriteBackListener] autosplitting dnt_mongodb.posts1 size: 54106804 shard: ns:dnt_mongodb.posts1 at: shard0000:10.0.4.85:27020 lastmod: 2|1min: { _id: 19 } max: { _id: MaxKey } on: { _id: 71452 }(splitThreshold 47185920)
Tue Sep 07 12:13:28 [WriteBackListener] config change: { _id: "4_85-2010-09-07T04:13:28-1", server: "4_85", time: new Date(1283832808738), what: "split", ns: "dnt_mongodb.posts1", details: { before: { min: { _id: 19 }, max: { _id: MaxKey }}, left: { min: { _id: 19 }, max: { _id: 71452 } }, right: { min: { _id: 71452 }, max: { _id: MaxKey } } } }
Tue Sep 07 12:13:15 [conn14] config change: { _id: "4_85-2010-09-07T04:13:15-0", server: "4_85", time: new Date(1283832795994), what: "split", ns: "dnt_mongodb.posts1", details: { before: { min: { _id: MinKey }, max: { _id: MaxKey } }, left: { min: { _id: MinKey }, max: { _id: 19 } }, right: { min: { _id: 19 }, max: {_id: MaxKey } } } }
Tue Sep 07 12:13:16 [conn14] moving chunk (auto): ns:dnt_mongodb.posts1 at: shard0000:10.0.4.85:27020 lastmod: 1|1 min: { _id: MinKey } max: { _id: 19 } to: shard0001:10.0.4.85:27021 #objects: 0
Tue Sep 07 12:13:16 [conn14] moving chunk ns: dnt_mongodb.posts1 moving ( ns:dnt_mongodb.posts1 at: shard0000:10.0.4.85:27020 lastmod: 1|1 min: { _id: MinKey }max: { _id: 19 }) shard0000:10.0.4.85:27020 -> shard0001:10.0.4.85:27021
Tue Sep 07 12:13:23 [WriteBackListener] ~ScopedDBConnection: _conn != null
Tue Sep 07 12:13:23 [WriteBackListener] ERROR: splitIfShould failed: ns: dnt_mongodb.posts1 findOne has stale config
Tue Sep 07 12:13:28 [WriteBackListener] autosplitting dnt_mongodb.posts1 size: 54106804 shard: ns:dnt_mongodb.posts1 at: shard0000:10.0.4.85:27020 lastmod: 2|1min: { _id: 19 } max: { _id: MaxKey } on: { _id: 71452 }(splitThreshold 47185920)
Tue Sep 07 12:13:28 [WriteBackListener] config change: { _id: "4_85-2010-09-07T04:13:28-1", server: "4_85", time: new Date(1283832808738), what: "split", ns: "dnt_mongodb.posts1", details: { before: { min: { _id: 19 }, max: { _id: MaxKey }}, left: { min: { _id: 19 }, max: { _id: 71452 } }, right: { min: { _id: 71452 }, max: { _id: MaxKey } } } }
