MongoDB实战系列之五：mongodb的分片配置

md01    10.0.0.11
md02    10.0.0.12
md03    10.0.0.14

2、启动三台机器的mongod实例

根据Replica Set、Sharding策略部署mongod。将两个sharding组部署到三台服务器上，每个sharding组有三个replica set成员。

#Server1:

mkdir -p /elain/data/mongodb/shard11
mkdir -p /elain/data/mongodb/shard21
/elain/apps/mongodb/bin/mongod --shardsvr --replSet shard1 --port 27017 --dbpath /elain/data/mongodb/shard11 --oplogSize 100 --logpath /elain/data/mongodb/shard11.log --logappend --fork --rest
/elain/apps/mongodb/bin/mongod --shardsvr --replSet shard2 --port 27018 --dbpath /elain/data/mongodb/shard21 --oplogSize 100 --logpath /elain/data/mongodb/shard21.log --logappend --fork --rest

#Server2:

mkdir -p /elain/data/mongodb/shard12/
mkdir -p /elain/data/mongodb/shard22/
/elain/apps/mongodb/bin/mongod --shardsvr --replSet shard1 --port 27017 --dbpath /elain/data/mongodb/shard12 --oplogSize 100 --logpath /elain/data/mongodb/shard12.log --logappend --fork --rest
/elain/apps/mongodb/bin/mongod --shardsvr --replSet shard2 --port 27018 --dbpath /elain/data/mongodb/shard22 --oplogSize 100 --logpath /elain/data/mongodb/shard22.log --logappend --fork --rest

#Server3:

mkdir -p /elain/data/mongodb/shard13/
mkdir -p /elain/data/mongodb/shard23/
/elain/apps/mongodb/bin/mongod --shardsvr --replSet shard1 --port 27017 --dbpath /elain/data/mongodb/shard13 --oplogSize 100 --logpath /elain/data/mongodb/shard13.log --logappend --fork --rest
/elain/apps/mongodb/bin/mongod --shardsvr --replSet shard2 --port 27018 --dbpath /elain/data/mongodb/shard23 --oplogSize 100 --logpath /elain/data/mongodb/shard23.log --logappend --fork --rest

/elain/apps/mongodb/bin/mongo 10.0.0.11:27017

config = {_id: 'shard1', members: [
    {_id: 0, host: '10.0.0.11:27017'},
    {_id: 1, host: '10.0.0.12:27017'},
    {_id: 2, host: '10.0.0.14:27017'}]};

rs.initiate(config);

/elain/apps/mongodb/bin/mongo 10.0.0.11:27018

config = {_id: 'shard2', members: [
    {_id: 0, host: '10.0.0.11:27018'},
    {_id: 1, host: '10.0.0.12:27018'},
    {_id: 2, host: '10.0.0.14:27018'}]};

rs.initiate(config);

4、启动并配置三台Config Server

#Server1、2、3:

mkdir -p /elain/data/mongodb/config/
/elain/apps/mongodb/bin/mongod --configsvr --dbpath /elain/data/mongodb/config/ --port 20000 --logpath /elain/data/mongodb/config1.log --logappend --fork

5、部署并配置三台Routing Server

指定所有的config sever地址参数，chunkSize是分割数据时每块(Chunk)的单位大小

#Server1、2、3:

/elain/apps/mongodb/bin/mongos --configdb 10.0.0.11:20000,10.0.0.12:20000,10.0.0.14:20000 --port 30000 --chunkSize 100 --logpath /elain/data/mongodb/mongos.log --logappend --fork

6、命令行添加分片

连接到mongs服务器，并切换到admin

/elain/apps/mongodb/bin/mongo 10.0.0.11:30000/admin

db.runCommand( {
    addshard : "shard1/10.0.0.11:27017,10.0.0.12:27017,10.0.0.14:27017",
    name:"shard1",
    maxsize:2048,
    allowLocal:true } );

db.runCommand( {
    addshard : "shard2/10.0.0.11:27018,10.0.0.12:27018,10.0.0.14:27018",
    name:"shard2",
    maxsize:2048,
    allowLocal:true } );

db.runCommand( { listshards : 1 } );

db.runCommand( { enablesharding : "elain" } );

要使单个collection也分片存储，需要给collection指定一个分片key，通过以下命令操作：

db.runCommand( { shardcollection : “<namespace>”,key : <shardkeypatternobject});

注：
 a. 分片的collection系统会自动创建一个索引（也可用户提前创建好）
 b. 分片的collection只能有一个在分片key上的唯一索引，其它唯一索引不被允许
One note: a sharded collection can have only one unique index, which must exist on the shard key. No other unique indexes can exist on the collection.

mongoimport -d elain -c test --type csv --headerline --file test.csv --host 10.0.0.11:30000

分片collection例子

db.runCommand( { shardcollection : "elain.test",key : {id: 1} } )
mongos> db.chujq.t1.stats();
{
        "sharded" : true,
        "flags" : 1,
        "ns" : "elain.test",
        "count" : 4058977,
        "numExtents" : 34,
        "size" : 675039816,
        "storageSize" : 818757632,
        "totalIndexSize" : 131854352,
        "indexSizes" : {
                "_id_" : 131854352
        },
        "avgObjSize" : 166.30786919955446,
        "nindexes" : 1,
        "nchunks" : 14,
        "shards" : {
                "shard1" : {
                        "ns" : "elain.test",
                        "count" : 1860365,
                        "size" : 309376352,
                        "avgObjSize" : 166.29873815084673,
                        "storageSize" : 408920064,
                        "numExtents" : 16,
                        "nindexes" : 1,
                        "lastExtentSize" : 77955072,
                        "paddingFactor" : 1,
                        "flags" : 1,
                        "totalIndexSize" : 60371584,
                        "indexSizes" : {
                                "_id_" : 60371584
                        },
                        "ok" : 1
                },
                "shard2" : {
                        "ns" : "elain.test",
                        "count" : 2198612,
                        "size" : 365663464,
                        "avgObjSize" : 166.31559547569103,
                        "storageSize" : 409837568,
                        "numExtents" : 18,
                        "nindexes" : 1,
                        "lastExtentSize" : 74846208,
                        "paddingFactor" : 1,
                        "flags" : 1,
                        "totalIndexSize" : 71482768,
                        "indexSizes" : {
                                "_id_" : 71482768
                        },
                        "ok" : 1
                }
        },
        "ok" : 1
}

删除片操作

mongos> db.runCommand({"removeshard" : "10.0.0.11:27018"});
{
        "msg" : "draining started successfully",
        "state" : "started",
        "shard" : "shard2",
        "ok" : 1
}

再执行，可看到removeshard的挪动进度

mongos> db.runCommand({"removeshard" : "10.0.0.11:27018"});
{
        "msg" : "draining ongoing",
        "state" : "ongoing",
        "remaining" : {
                "chunks" : NumberLong(3),
                "dbs" : NumberLong(0)
        },
        "ok" : 1
}

例:

/elain/apps/mongodb/bin/mongod --config /elain/data/mongodb/shard1/shard1.properties --rest