mongodb副本集+分片集羣部署 step by step

mongodb副本集+分片集羣部署step by step

本文只講述mongodb副本集+分片集羣的部署，關於mongdb shading & replica set原理優點等不在本文討論範圍內。
MongoDB Sharding Cluster，需要三種角色：

Shard Server: mongod 實例，用於存儲實際的數據塊，實際生產環境中一個shard server角色可由幾臺機器組個一個relica set承擔，防止主機單點故障

Config Server: mongod 實例，存儲了整個 Cluster Metadata，其中包括 chunk 信息。

Route Server: mongos 實例，前端路由，客戶端由此接入，且讓整個集羣看上去像單一數據庫，前端應用可以透明使用。

本實例用的機器：

分別在3臺機器運行一個mongod實例（稱爲mongod shard11，mongod shard12，mongod shard13）組織replica set1，作爲cluster的shard1
分別在3臺機器運行一個mongod實例（稱爲mongod shard21，mongod shard22，mongod shard23）組織replica set2，作爲cluster的shard2
每臺機器運行一個mongod實例，作爲3個config server
每臺機器運行一個mongs進程，用於客戶端連接

1、安裝mongodb
使用mongodb的版本 mongodb-linux-x86_64-rhel62-3.0.7.tgz
將mongodb-linux-x86_64-rhel62-3.0.7.tgz 解壓到 /home/services
Server1、Server2、Server3 均作如下操作：
cd /home/services/
tar -zxf mongodb-linux-x86_64-rhel62-3.0.7.tgz
mv mongodb-linux-x86_64-rhel62-3.0.7 mongodb

2、創建sharding數據目錄
根據本例sharding架構圖所示，在各臺sever上創建shard數據文件目錄
Server1:
cd /home/services/mongodb
mkdir -p data/shard11
mkdir -p data/shard21

Server2:
cd /home/services/mongodb
mkdir -p data/shard12
mkdir -p data/shard22

Server3:
cd /home/services/mongodb
mkdir -p data/shard13
mkdir -p data/shard23

3、配置relica sets
3.1 配置shard1所用到的replica sets 1:
server1:
./bin/mongod –shardsvr –replSet shard1 –port 27018 –dbpath /home/services/mongodb/data/shard11 –oplogSize 100 –logpath /home/services/mongodb/data/shard11.log –logappend –fork
server2:
./bin/mongod –shardsvr –replSet shard1 –port 27018 –dbpath /home/services/mongodb/data/shard12 –oplogSize 100 –logpath /home/services/mongodb/data/shard12.log –logappend –fork
server3:
./bin/mongod –shardsvr –replSet shard1 –port 27018 –dbpath /home/services/mongodb/data/shard13 –oplogSize 100 –logpath /home/services/mongodb/data/shard13.log –logappend –fork

3.2 初始化replica set 1

連接到一臺mongod
./mongo –port 27018
執行如下腳本

config = {
         "_id" : "shard1",
         "members" : [
                 {
                         "_id" : 0,
                         "host" : "192.168.66.10:27018"
                 },
                 {
                         "_id" : 1,
                         "host" : "192.168.66.20:27018"
                 },
                 {
                         "_id" : 2,
                         "host" : "192.168.66.30:27018"
                 }
         ]
 }

 rs.initiate(config);

3.3 配置shard2所用到的replica sets 2:
server1:
./bin/mongod –shardsvr –replSet shard2 –port 27019 –dbpath /home/services/mongodb/data/shard21 –oplogSize 100 –logpath /home/services/mongodb/data/shard21.log –logappend –fork
server2:
./bin/mongod –shardsvr –replSet shard2 –port 27019 –dbpath /home/services/mongodb/data/shard22 –oplogSize 100 –logpath /home/services/mongodb/data/shard22.log –logappend –fork
server3:
./bin/mongod –shardsvr –replSet shard2 –port 27019 –dbpath /home/services/mongodb/data/shard23 –oplogSize 100 –logpath /home/services/mongodb/data/shard23.log –logappend –fork

3.4 初始化replica set 2

連接到一臺mongod
./mongo –port 27019
執行如下腳本

config = {
         "_id" : "shard2",
         "members" : [
                 {
                         "_id" : 0,
                         "host" : "192.168.66.10:27019"
                 },
                 {
                         "_id" : 1,
                         "host" : "192.168.66.20:27019"
                 },
                 {
                         "_id" : 2,
                         "host" : "192.168.66.30:27019"
                 }
         ]
 }

 rs.initiate(config);

4、配置三臺config server

Server1:
mkdir -p /home/services/mongodb/data/config
./bin/mongod –configsvr –dbpath /home/services/mongodb/data/config –port 20000 –logpath /home/services/mongodb/data/config.log –logappend –fork

Server2:
mkdir -p /home/services/mongodb/data/config
./bin/mongod –configsvr –dbpath /home/services/mongodb/data/config –port 20000 –logpath /home/services/mongodb/data/config.log –logappend –fork

Server3:
mkdir -p /home/services/mongodb/data/config
./bin/mongod –configsvr –dbpath /home/services/mongodb/data/config –port 20000 –logpath /home/services/mongodb/data/config.log –logappend –fork

5、配置mongs
在server1,server2,server3上分別執行：
./bin/mongos –configdb 192.168.66.10:20000,192.168.66.20:20000,192.168.66.30:20000 –port 27017 –chunkSize 5 –logpath /home/services/mongodb/data/mongos.log –logappend –fork

6、配置分片集羣（Configuring the Shard Cluster）
連接到其中一個mongos進程，並切換到admin數據庫做以下配置
6.1、連接到mongs，並切換到admin
./bin/mongo 192.168.66.10:27017/admin

db
Admin
6.2、 加入shards
如裏shard是單臺服務器，用>db.runCommand( { addshard : “[:]” } )這樣的命令加入，如果shard是replica sets，用replicaSetName/[:port][,serverhostname2[:port],…]這樣的格式表示，例如本例執行：

>db.runCommand( { addshard:"shard1/192.168.66.10:27018,192.168.66.20:27018,192.168.66.30:27018",name:"s1",maxsize:20480});
>db.runCommand( { addshard:"shard2/192.168.66.10:27019,192.168.66.20:27019,192.168.66.30:27019",name:"s2",maxsize:20480});

注：
可選參數
Name:用於指定每個shard的名字，不指定的話系統將自動分配
maxSize:指定各個shard可使用的最大磁盤空間，單位megabytes

6.3、 Listing shards

db.runCommand( { listshards : 1 } )
如果列出了以上二個你加的shards，表示shards已經配置成功

如下爲執行效果

[root@appsvr mongodb]# ./bin/mongo 192.168.66.10:27017/admin
mongos> db
admin
mongos> db.runCommand( { addshard:"shard1/192.168.66.10:27018,192.168.66.20:27018,192.168.66.30:27018",name:"s1",maxsize:20480});
{ "shardAdded" : "s1", "ok" : 1 }
mongos> db.runCommand( { addshard:"shard2/192.168.66.10:27019,192.168.66.20:27019,192.168.66.30:27019",name:"s2",maxsize:20480});
{ "shardAdded" : "s2", "ok" : 1 }
mongos> db.runCommand( { listshards : 1 } )
{
        "shards" : [
                {
                        "_id" : "s1",
                        "host" : "shard1/192.168.66.10:27018,192.168.66.20:27018,192.168.66.30:27018"
                },
                {
                        "_id" : "s2",
                        "host" : "shard2/192.168.66.10:27019,192.168.66.20:27019,192.168.66.30:27019"
                }
        ],
        "ok" : 1
}
mongos>

6.4、 激活數據庫分片
命令：

db.runCommand( { enablesharding : “” } );
通過執行以上命令，可以讓數據庫跨shard，如果不執行這步，數據庫只會存放在一個shard，一旦激活數據庫分片，數據庫中不同的collection將被存放在不同的shard上，但一個collection仍舊存放在同一個shard上，要使單個collection也分片，還需單獨對collection作些操作

Collecton分片
要使單個collection也分片存儲，需要給collection指定一個分片key，通過以下命令操作：

db.runCommand( { shardcollection : “”,key : });
注：
a. 分片的collection系統會自動創建一個索引（也可用戶提前創建好）
b. 分片的collection只能有一個在分片key上的唯一索引，其它唯一索引不被允許

例子：

mongos> db.runCommand({enablesharding:"test2"});
{ "ok" : 1 }
mongos> db.runCommand( { shardcollection : "test2.books", key : { id : 1 } } );
{ "collectionsharded" : "test2.books", "ok" : 1 }
mongos> use test2
switched to db test2
mongos> db.stats();
{
        "raw" : {
                "shard1/192.168.66.10:27018,192.168.66.20:27018,192.168.66.30:27018" : {
                        "db" : "test2",
                        "collections" : 3,
                        "objects" : 6,
                        "avgObjSize" : 69.33333333333333,
                        "dataSize" : 416,
                        "storageSize" : 20480,
                        "numExtents" : 3,
                        "indexes" : 2,
                        "indexSize" : 16352,
                        "fileSize" : 67108864,
                        "nsSizeMB" : 16,
                        "extentFreeList" : {
                                "num" : 0,
                                "totalSize" : 0
                        },
                        "dataFileVersion" : {
                                "major" : 4,
                                "minor" : 22
                        },
                        "ok" : 1,
                        "$gleStats" : {
                                "lastOpTime" : Timestamp(0, 0),
                                "electionId" : ObjectId("586286596422d63aa9f9f000")
                        }
                },
                "shard2/192.168.66.10:27019,192.168.66.20:27019,192.168.66.30:27019" : {
                        "db" : "test2",
                        "collections" : 0,
                        "objects" : 0,
                        "avgObjSize" : 0,
                        "dataSize" : 0,
                        "storageSize" : 0,
                        "numExtents" : 0,
                        "indexes" : 0,
                        "indexSize" : 0,
                        "fileSize" : 0,
                        "ok" : 1
                }
        },
        "objects" : 6,
        "avgObjSize" : 69,
        "dataSize" : 416,
        "storageSize" : 20480,
        "numExtents" : 3,
        "indexes" : 2,
        "indexSize" : 16352,
        "fileSize" : 67108864,
        "extentFreeList" : {
                "num" : 0,
                "totalSize" : 0
        },
        "ok" : 1
}
mongos> db.books.stats();
{
        "sharded" : true,
        "paddingFactorNote" : "paddingFactor is unused and unmaintained in 3.0. It remains hard coded to 1.0 for c                                        ompatibility only.",
        "userFlags" : 1,
        "capped" : false,
        "ns" : "test2.books",
        "count" : 0,
        "numExtents" : 1,
        "size" : 0,
        "storageSize" : 8192,
        "totalIndexSize" : 16352,
        "indexSizes" : {
                "_id_" : 8176,
                "id_1" : 8176
        },
        "avgObjSize" : 0,
        "nindexes" : 2,
        "nchunks" : 1,
        "shards" : {
                "s1" : {
                        "ns" : "test2.books",
                        "count" : 0,
                        "size" : 0,
                        "numExtents" : 1,
                        "storageSize" : 8192,
                        "lastExtentSize" : 8192,
                        "paddingFactor" : 1,
                        "paddingFactorNote" : "paddingFactor is unused and unmaintained in 3.0. It remains hard co                                        ded to 1.0 for compatibility only.",
                        "userFlags" : 1,
                        "capped" : false,
                        "nindexes" : 2,
                        "totalIndexSize" : 16352,
                        "indexSizes" : {
                                "_id_" : 8176,
                                "id_1" : 8176
                        },
                        "ok" : 1,
                        "$gleStats" : {
                                "lastOpTime" : Timestamp(0, 0),
                                "electionId" : ObjectId("586286596422d63aa9f9f000")
                        }
                }
        },
        "ok" : 1
}

7、測試

mongos> for (var i = 1; i <= 20000; i++) db.books.save({id:i,name:"12345678",sex:"male",age:27,value:"test"});
WriteResult({ "nInserted" : 1 })
mongos> db.books.stats();
{
        "sharded" : true,
        "paddingFactorNote" : "paddingFactor is unused and unmaintained in 3.0. It remains hard coded to 1.0 for compatibility only.",
        "userFlags" : 1,
        "capped" : false,
        "ns" : "test2.books",
        "count" : 20000,
        "numExtents" : 10,
        "size" : 2240000,
        "storageSize" : 5586944,
        "totalIndexSize" : 1250928,
        "indexSizes" : {
                "_id_" : 670432,
                "id_1" : 580496
        },
        "avgObjSize" : 112,
        "nindexes" : 2,
        "nchunks" : 5,
        "shards" : {
                "s1" : {
                        "ns" : "test2.books",
                        "count" : 12300,
                        "size" : 1377600,
                        "avgObjSize" : 112,
                        "numExtents" : 5,
                        "storageSize" : 2793472,
                        "lastExtentSize" : 2097152,
                        "paddingFactor" : 1,
                        "paddingFactorNote" : "paddingFactor is unused and unmaintained in 3.0. It remains hard coded to 1.0 for compatibility only.",
                        "userFlags" : 1,
                        "capped" : false,
                        "nindexes" : 2,
                        "totalIndexSize" : 760368,
                        "indexSizes" : {
                                "_id_" : 408800,
                                "id_1" : 351568
                        },
                        "ok" : 1,
                        "$gleStats" : {
                                "lastOpTime" : Timestamp(0, 0),
                                "electionId" : ObjectId("586286596422d63aa9f9f000")
                        }
                },
                "s2" : {
                        "ns" : "test2.books",
                        "count" : 7700,
                        "size" : 862400,
                        "avgObjSize" : 112,
                        "numExtents" : 5,
                        "storageSize" : 2793472,
                        "lastExtentSize" : 2097152,
                        "paddingFactor" : 1,
                        "paddingFactorNote" : "paddingFactor is unused and unmaintained in 3.0. It remains hard coded to 1.0 for compatibility only.",
                        "userFlags" : 1,
                        "capped" : false,
                        "nindexes" : 2,
                        "totalIndexSize" : 490560,
                        "indexSizes" : {
                                "_id_" : 261632,
                                "id_1" : 228928
                        },
                        "ok" : 1,
                        "$gleStats" : {
                                "lastOpTime" : Timestamp(0, 0),
                                "electionId" : ObjectId("58628704f916bb05014c5ea7")
                        }
                }
        },
        "ok" : 1
}