Mongodb高可用架构—Replica Set 集群实战

Replica Set使用的是n个mongod节点，构建具备自动的容错功能(auto-failover),自动恢复的(auto-recovery)的高可用方案。

使用Replica Set来实现读写分离。通过在连接时指定或者在主库指定slaveOk，由Secondary来分担读的压力，Primary只承担写操作。

对于Replica Set中的secondary 节点默认是不可读的。 

 

 

架构图：

 

分别在各服务器上运行两个mongod实例: 

shard11 + shard12 + shard13 ----> 组成一个replica set --|

   |-----> sharding_cluster

shard21 + shard22 + shard23 ----> 组成一个replica set --|

 

Shard Server: 用于存储实际的数据块，实际生产环境中一个shard server角色可由几台机器组个一个relica set承担，防止主机单点故障!

Config Server: 存储了整个 Cluster Metadata，其中包括 chunk 信息!

Route Server: 前端路由，客户端由此接入，且让整个集群看上去像单一数据库，前端应用可以透明使用。

 

一、安装配置mongodb环境

1.安装

wget http://fastdl.mongodb.org/linux/mongodb-linux-x86_64-2.0.4.tgz
tar zxf mongodb-linux-x86_64-2.0.4.tgz
mv mongodb-linux-x86_64-2.0.4 /opt/mongodb
echo "export PATH=$PATH:/opt/mongodb/bin" >> /etc/profile
source /etc/profile

2.建立用户和组

useradd -u 600 -s /bin/false mongodb

3.创建数据目录

在各服务器上建立如下目录：

30服务器:
mkdir -p /data0/mongodb/{db,logs}
mkdir -p /data0/mongodb/db/{shard11,shard21,config}
31服务器:
mkdir -p /data0/mongodb/{db,logs}
mkdir -p /data0/mongodb/db/{shard12,shard22,config}
32服务器:
mkdir -p /data0/mongodb/{db,logs}
mkdir -p /data0/mongodb/db/{shard13,shard23,config}

4.设置各节点服务器hosts解析

 

true > /etc/hosts
echo -ne "
192.168.8.30     mong01
192.168.8.31     mong02
192.168.8.32     mong03
" >>/etc/hosts

或
cat >> /etc/hosts << EOF
192.168.8.30     mong01
192.168.8.31     mong02
192.168.8.32     mong03
EOF

5.同步时钟

ntpdate ntp.api.bz

写到crontab任务计划中！

这里务必要同步时钟，不然shrad不能同步！

 

以上配置各节点都进行操作！！

 

二、配置relica sets

1.配置两个shard

30 server:
/opt/mongodb/bin/mongod -shardsvr -replSet shard1 -port 27021 -dbpath /data0/mongodb/db/shard11 -oplogSize 1000 -logpath /data0/mongodb/logs/shard11.log -logappend  --maxConns 10000 --quiet -fork --directoryperdb
sleep 2
/opt/mongodb/bin/mongod -shardsvr -replSet shard2 -port 27022 -dbpath /data0/mongodb/db/shard21 -oplogSize 1000 -logpath /data0/mongodb/logs/shard21.log -logappend  --maxConns 10000 --quiet -fork --directoryperdb
sleep 2
echo "all mongo started."

31 server:
/opt/mongodb/bin/mongod -shardsvr -replSet shard1 -port 27021 -dbpath /data0/mongodb/db/shard12 -oplogSize 1000 -logpath /data0/mongodb/logs/shard12.log -logappend  --maxConns 10000 --quiet -fork --directoryperdb
sleep 2
numactl --interleave=all /opt/mongodb/bin/mongod -shardsvr -replSet shard2 -port 27022 -dbpath /data0/mongodb/db/shard22 -oplogSize 1000 -logpath /data0/mongodb/logs/shard22.log -logappend  --maxConns 10000 --quiet -fork --directoryperdb
sleep 2
echo "all mongo started."

32 server:
numactl --interleave=all /opt/mongodb/bin/mongod -shardsvr -replSet shard1 -port 27021 -dbpath /data0/mongodb/db/shard13 -oplogSize 1000 -logpath /data0/mongodb/logs/shard13.log -logappend  --maxConns 10000 --quiet -fork --directoryperdb
sleep 2
numactl --interleave=all /opt/mongodb/bin/mongod -shardsvr -replSet shard2 -port 27022 -dbpath /data0/mongodb/db/shard23 -oplogSize 1000 -logpath /data0/mongodb/logs/shard23.log -logappend  --maxConns 10000 --quiet -fork --directoryperdb
sleep 2
echo "all mongo started."

 

可以对应的把上面的命令放在一个脚本内，方便启动！

也可以写到配置文件中，通过-f参数来启动！

改成配置文件方式：

shardsvr = true
replSet = shard1
port = 27021
dbpath = /data0/mongodb/db/shard11
oplogSize = 1000
logpath = /data0/mongodb/logs/shard11.log
logappend = true
maxConns = 10000
quit=true
profile = 1
slowms = 5
rest = true
fork = true
directoryperdb = true

这样可以通过 mognod -f mongodb.conf来启动了！

 

我这里把这些命令都放入脚本中：

启动脚本(这里只启动mongod,后面有专门启动config和mongos脚本)：

 

[root@mon1 sh]# cat start.sh
/opt/mongodb/bin/mongod -shardsvr -replSet shard1 -port 27021 -dbpath /data0/mongodb/db/shard11 -oplogSize 1000 -logpath /data0/mongodb/logs/shard11.log -logappend  --maxConns 10000 --quiet -fork --directoryperdb
sleep 2

/opt/mongodb/bin/mongod -shardsvr -replSet shard2 -port 27022 -dbpath /data0/mongodb/db/shard21 -oplogSize 1000 -logpath /data0/mongodb/logs/shard21.log -logappend  --maxConns 10000 --quiet -fork --directoryperdb
sleep 2
ps aux |grep mongo
echo "all mongo started."

[root@mon2 sh]# cat start.sh
/opt/mongodb/bin/mongod -shardsvr -replSet shard1 -port 27021 -dbpath /data0/mongodb/db/shard12 -oplogSize 1000 -logpath /data0/mongodb/logs/shard12.log -logappend  --maxConns 10000 --quiet -fork --directoryperdb
sleep 2
/opt/mongodb/bin/mongod -shardsvr -replSet shard2 -port 27022 -dbpath /data0/mongodb/db/shard22 -oplogSize 1000 -logpath /data0/mongodb/logs/shard22.log -logappend  --maxConns 10000 --quiet -fork --directoryperdb
sleep 2
ps aux |grep mongo
echo "all mongo started."

[root@mongo03 sh]# cat start.sh
/opt/mongodb/bin/mongod -shardsvr -replSet shard1 -port 27021 -dbpath /data0/mongodb/db/shard11 -oplogSize 1000 -logpath /data0/mongodb/logs/shard11.log -logappend  --maxConns 10000 --quiet -fork --directoryperdb  --keyFile=/opt/mongodb/sh/keyFile
sleep 2
/opt/mongodb/bin/mongod -shardsvr -replSet shard2 -port 27022 -dbpath /data0/mongodb/db/shard21 -oplogSize 1000 -logpath /data0/mongodb/logs/shard21.log -logappend  --maxConns 10000 --quiet -fork --directoryperdb  --keyFile=/opt/mongodb/sh/keyFile
sleep 2
echo "all mongo started."

 

PS：要是想开启一个HTTP协议的端口提供rest服务，可以在mongod启动参数中加上 --rest 选项！

这样我们可以通过 http://IP:28021/_replSet 查看状态！

 

生产环境推荐用配置文件和脚本文件方式启动。

 

三、初始化replica set

 

1.配置shard1用到的replica sets

 

[root@mongo01 ~]# mongo 192.168.8.30:27021
> config = {_id: 'shard1', members: [
    {_id: 0, host: '192.168.8.30:27021'},
    {_id: 1, host: '192.168.8.31:27021'},
    {_id: 2, host: '192.168.8.32:27021'}]
  }

> config = {_id: 'shard1', members: [
...                           {_id: 0, host: '192.168.8.30:27021'},
...                           {_id: 1, host: '192.168.8.31:27021'},
...                           {_id: 2, host: '192.168.8.32:27021'}]
...            }
{
    "_id" : "shard1",
    "members" : [
        {
            "_id" : 0,
            "host" : "192.168.8.30:27021"
        },
        {
            "_id" : 1,
            "host" : "192.168.8.31:27021"
        },
        {
            "_id" : 2,
            "host" : "192.168.8.32:27021"
        }
    ]
}

出现如下信息表示成功： 

> rs.initiate(config)
{
    "info" : "Config now saved locally.  Should come online in about a minute.",
    "ok" : 1
}


> rs.status()
{
    "set" : "shard1",
    "date" : ISODate("2012-06-07T11:35:22Z"),
    "myState" : 1,
    "members" : [
        {
            "_id" : 0,
            "name" : "192.168.8.30:27021",
            "health" : 1,  #1 表示正常
            "state" : 1,   #1 表示是primary
            "stateStr" : "PRIMARY",  #表示此服务器是主库
            "optime" : {
                "t" : 1339068873000,
                "i" : 1
            },
            "optimeDate" : ISODate("2012-06-07T11:34:33Z"),
            "self" : true
        },
        {
            "_id" : 1,
            "name" : "192.168.8.31:27021",
            "health" : 1,    #1 表示正常
            "state" : 2,     #2 表示是secondary
            "stateStr" : "SECONDARY",  #表示此服务器是从库
            "uptime" : 41,
            "optime" : {
                "t" : 1339068873000,
                "i" : 1
            },
            "optimeDate" : ISODate("2012-06-07T11:34:33Z"),
            "lastHeartbeat" : ISODate("2012-06-07T11:35:21Z"),
            "pingMs" : 7
        },
        {
            "_id" : 2,
            "name" : "192.168.8.32:27021",
            "health" : 1,
            "state" : 2,
            "stateStr" : "SECONDARY",
            "uptime" : 36,
            "optime" : {
                "t" : 1341373105000,
                "i" : 1
            },
            "optimeDate" : ISODate("2012-06-07T11:34:00Z"),
            "lastHeartbeat" : ISODate("2012-06-07T11:35:21Z"),
            "pingMs" : 3
        }
    ],
    "ok" : 1
}
PRIMARY>

可以看马上变成 PRIMARY 即主节点！

再到其它节点看下： 

[root@mongo02 sh]# mongo 192.168.8.31:27021
MongoDB shell version: 2.0.5
connecting to: 192.168.8.31:27021/test
SECONDARY>

[root@mongo03 sh]# mongo 192.168.8.32:27021
MongoDB shell version: 2.0.5
connecting to: 192.168.8.32:27021/test
SECONDARY>

在所有节点上可以查看Replica Sets 的配置信息: 

PRIMARY> rs.conf()
{
    "_id" : "shard1",
    "version" : 1,
    "members" : [
        {
            "_id" : 0,
            "host" : "192.168.8.30:27021"
        },
        {
            "_id" : 1,
            "host" : "192.168.8.31:27021"
        },
        {
            "_id" : 2,
            "host" : "192.168.8.32:27021",
            "shardOnly" : true
        }
    ]
}

2.配置shard2用到的replica sets

 

[root@mongo02 sh]# mongo 192.168.8.30:27022
MongoDB shell version: 2.0.5
connecting to: 192.168.8.30:27022/test
> config = {_id: 'shard2', members: [
    {_id: 0, host: '192.168.8.30:27022'},
    {_id: 1, host: '192.168.8.31:27022'},
    {_id: 2, host: '192.168.8.32:27022'}]
    }
> config = {_id: 'shard2', members: [
... {_id: 0, host: '192.168.8.30:27022'},
... {_id: 1, host: '192.168.8.31:27022'},
... {_id: 2, host: '192.168.8.32:27022'}]
... }
{
    "_id" : "shard2",
    "members" : [
        {
            "_id" : 0,
            "host" : "192.168.8.30:27022"
        },
        {
            "_id" : 1,
            "host" : "192.168.8.31:27022"
        },
        {
            "_id" : 2,
            "host" : "192.168.8.32:27022"
        }
    ]
}

> rs.initiate(config)
{
    "info" : "Config now saved locally.  Should come online in about a minute.",
    "ok" : 1
}

验证节点：

 

> rs.status()
{
    "set" : "shard2",
    "date" : ISODate("2012-06-07T11:43:47Z"),
    "myState" : 2,
    "members" : [
        {
            "_id" : 0,
            "name" : "192.168.8.30:27022",
            "health" : 1,
            "state" : 1,
            "stateStr" : "PRIMARY",
            "optime" : {
                "t" : 1341367921000,
                "i" : 1
            },
            "optimeDate" : ISODate("2012-06-07T11:43:40Z"),
            "self" : true
        },
        {
            "_id" : 1,
            "name" : "192.168.8.31:27022",
            "health" : 1,
            "state" : 2,
            "stateStr" : "SECONDARY",
            "uptime" : 50,
            "optime" : {
                "t" : 1341367921000,
                "i" : 1
            },
            "optimeDate" : ISODate("1970-01-01T00:00:00Z"),
            "lastHeartbeat" : ISODate("2012-06-07T11:43:46Z"),
            "pingMs" : 0,
        },
        {
            "_id" : 2,
            "name" : "192.168.8.32:27022",
            "health" : 1,
            "state" : 2,
            "stateStr" : "SECONDARY",
            "uptime" : 81,
            "optime" : {
                "t" : 1341373254000,
                "i" : 1
            },
            "optimeDate" : ISODate("2012-06-07T11:41:00Z"),
            "lastHeartbeat" : ISODate("2012-06-07T11:43:46Z"),
            "pingMs" : 0,
        }
    ],
    "ok" : 1
}
PRIMARY>

到此就配置好了二个replica sets！

PS: 初始化时，不指定priority默认id 0 为primary

 

状态中关键数据位:

在用 rs.status()查看replica sets状态时，

state：1表示该host是当前可以进行读写，2：不能读写

health：1表示该host目前是正常的，0:异常

 

注意：初使化replica sets时也可以用这种方法：

db.runCommand({"replSetInitiate":{"_id":"shard1","members":[{"_id":0,"host":"192.168.8.30:27021"},{"_id":1,"host":"192.168.8.31:27021"},{"_id":2,"host":"192.168.8.32:27021","shardOnly":true}]}})

可以省略用rs.initiate(config)。

 

四、配置三台config server

 

分别在各服务器上运行（启动都一样）：

/opt/mongodb/bin/mongod --configsvr --dbpath /data0/mongodb/db/config --port 20000 --logpath /data0/mongodb/logs/config.log --logappend --fork --directoryperdb

 

用脚本形式：

[root@mongo01 sh]# cat config.sh
/opt/mongodb/bin/mongod --configsvr --dbpath /data0/mongodb/db/config --port 20000 --logpath /data0/mongodb/logs/config.log --logappend --fork --directoryperdb
[root@mongo01 sh]# pwd
/opt/mongodb/sh
[root@mongo01 sh]# ./config.sh

 

然后在各节点查看有没有启动起来：

[root@mongo01 sh]# ps aux |grep mong
root     25343  0.9  6.8 737596 20036 ?        Sl   19:32   0:12 /opt/mongodb/bin/mongod -shardsvr -replSet shard1 -port 27021 -dbpath /data0/mongodb/db/shard1 -oplogSize 100 -logpath /data0/mongodb/logs/shard1.log -logappend --maxConns 10000 --quiet -fork --directoryperdb
root     25351  0.9  7.0 737624 20760 ?        Sl   19:32   0:11 /opt/mongodb/bin/mongod -shardsvr -replSet shard2 -port 27022 -dbpath /data0/mongodb/db/shard2 -oplogSize 100 -logpath /data0/mongodb/logs/shard2.log -logappend --maxConns 10000 --quiet -fork --directoryperdb
root     25669 13.0  4.7 118768 13852 ?        Sl   19:52   0:07 /opt/mongodb/bin/mongod --configsvr --dbpath /data0/mongodb/db/config --port 20000 --logpath /data0/mongodb/logs/config.log --logappend --fork --directoryperdb
root     25695  0.0  0.2  61220   744 pts/3    R+   19:53   0:00 grep mong

  

五、配置mongs（启动路由）

 

分别在206、207服务器上运行（也可以在所有节点上启动）：

/opt/mongodb/bin/mongos -configdb 192.168.8.30:20000,192.168.8.31:20000,192.168.8.32:20000 -port 30000 -chunkSize 50 -logpath /data0/mongodb/logs/mongos.log -logappend -fork

 

用脚本形式： 

[root@mongo01 sh]# cat mongos.sh
/opt/mongodb/bin/mongos -configdb 192.168.8.30:20000,192.168.8.31:20000,192.168.8.32:20000 -port 30000 -chunkSize 50 -logpath /data0/mongodb/logs/mongos.log -logappend -fork
[root@mongo01 sh]# pwd
/opt/mongodb/sh
[root@mongo01 sh]# ./mongos.sh
[root@mongo01 sh]# ps aux |grep mong
root     25343  0.8  6.8 737596 20040 ?        Sl   19:32   0:13 /opt/mongodb/bin/mongod -shardsvr -replSet shard1 -port 27021 -dbpath /data0/mongodb/db/shard1 -oplogSize 100 -logpath /data0/mongodb/logs/shard1.log -logappend --maxConns 10000 --quiet -fork --directoryperdb
root     25351  0.9  7.0 737624 20768 ?        Sl   19:32   0:16 /opt/mongodb/bin/mongod -shardsvr -replSet shard2 -port 27022 -dbpath /data0/mongodb/db/shard2 -oplogSize 100 -logpath /data0/mongodb/logs/shard2.log -logappend --maxConns 10000 --quiet -fork --directoryperdb
root     25669  2.0  8.0 321852 23744 ?        Sl   19:52   0:09 /opt/mongodb/bin/mongod --configsvr --dbpath /data0/mongodb/db/config --port 20000 --logpath /data0/mongodb/logs/config.log --logappend --fork --directoryperdb
root     25863  0.5  0.8  90760  2388 ?        Sl   20:00   0:00 /opt/mongodb/bin/mongos -configdb 192.168.8.30:20000,192.168.8.31:20000,192.168.8.32:20000 -port 30000 -chunkSize 50 -logpath /data0/mongodb/logs/mongos.log -logappend -fork
root     25896  0.0  0.2  61220   732 pts/3    D+   20:00   0:00 grep mong

注意：

1). mongos里面的ip和端口是config服务的ip和端口:192.168.8.30:20000,192.168.8.31:20000,192.168.8.32:20000

2). 必须先启动config后(并且config启动正常后，有config的进程存在)再启动mongos

 

六、配置shard集群 

1.连接一台路由 

[root@mongo01 sh]# mongo 192.168.8.30:30000/admin
MongoDB shell version: 2.0.5
connecting to: 192.168.8.30:30000/admin
mongos>

2.加入shards 

mongos> db.runCommand({ addshard : "shard1/192.168.8.30:27021,192.168.8.31:27021,192.168.8.32:27021",name:"shard1",maxSize:20480})
{ "shardAdded" : "shard1", "ok" : 1 }
mongos> db.runCommand({ addshard : "shard2/192.168.8.30:27022,192.168.8.31:27022,192.168.8.32:27022",name:"shard2",maxSize:20480})
{ "shardAdded" : "shard2", "ok" : 1 }

PS:

分片操作必须在 admin 库下操作

如果只启动206和207服务器的路由！因此可不用把208服务器加进来！

可选参数说明：

Name:用于指定每个shard的名字，不指定的话系统将自动分配

maxSize:指定各个shard可使用的最大磁盘空间，单位 MegaBytes

 

3.列出加入的shards 

mongos> db.runCommand( { listshards : 1 } );
{
    "shards" : [
        {
            "_id" : "shard1",
            "host" : "shard1/192.168.8.30:27021,192.168.8.31:27021,192.168.8.32:27021",
            "maxSize" : NumberLong(20480)
        },
        {
            "_id" : "shard2",
            "host" : "shard2/192.168.8.30:27022,192.168.8.31:27022,192.168.8.32:27022",
            "maxSize" : NumberLong(20480)
        }
    ],
    "ok" : 1
}

PS: 列出了以上二个我加的shards(shard1和shard2)，表示shards已经配置成功！！

如果206那台机器挂了，其它两个节点中某个会成为主节点，mongos会自动连接到主节点！

mongos> db.runCommand({ismaster:1});
{
    "ismaster" : true,
    "msg" : "isdbgrid",
    "maxBsonObjectSize" : 16777216,
    "ok" : 1
}
mongos> db.runCommand( { listshards : 1 } );
{ "ok" : 0, "errmsg" : "access denied - use admin db" }
mongos> use admin
switched to db admin
mongos> db.runCommand( { listshards : 1 } );
{
    "shards" : [
        {
            "_id" : "s1",
            "host" : "shard1/192.168.8.30:27021,192.168.8.31:27021"
        },
        {
            "_id" : "s2",
            "host" : "shard2/192.168.8.30:27022,192.168.8.31:27022"
        }
    ],
    "ok" : 1
}
mongos>

 

七.添加分片

 

1.激活数据库分片

db.runCommand( { enablesharding : "<dbname>" } );

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

 

插入测试数据：

mongos> use nosql
switched to db nosql
mongos> for(var i=0;i<100;i++)db.fans.insert({uid:i,uname:'nosqlfans'+i});

激活数据库：

mongos> use admin
switched to db admin
mongos> db.runCommand( { enablesharding : "nosql" } );
{ "ok" : 1 }

通过执行以上命令，可以让数据库跨shard，如果不执行这步，数据库只会存放在一个shard，一旦激活数据库分片，数据库中不同的collection 将被存放在不同的shard上，但一个collection仍旧存放在同一个shard上，要使单个collection也分片，还需单独对 collection作些操作!

 

2.添加索引

必须加索引，不然不能对collections分片！

mongos> use nosql
switched to db nosql
mongos> db.fans.find()
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad081"), "uid" : 0, "uname" : "nosqlfans0" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad082"), "uid" : 1, "uname" : "nosqlfans1" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad083"), "uid" : 2, "uname" : "nosqlfans2" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad084"), "uid" : 3, "uname" : "nosqlfans3" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad085"), "uid" : 4, "uname" : "nosqlfans4" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad086"), "uid" : 5, "uname" : "nosqlfans5" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad087"), "uid" : 6, "uname" : "nosqlfans6" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad088"), "uid" : 7, "uname" : "nosqlfans7" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad089"), "uid" : 8, "uname" : "nosqlfans8" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad08a"), "uid" : 9, "uname" : "nosqlfans9" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad08b"), "uid" : 10, "uname" : "nosqlfans10" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad08c"), "uid" : 11, "uname" : "nosqlfans11" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad08d"), "uid" : 12, "uname" : "nosqlfans12" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad08e"), "uid" : 13, "uname" : "nosqlfans13" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad08f"), "uid" : 14, "uname" : "nosqlfans14" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad090"), "uid" : 15, "uname" : "nosqlfans15" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad091"), "uid" : 16, "uname" : "nosqlfans16" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad092"), "uid" : 17, "uname" : "nosqlfans17" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad093"), "uid" : 18, "uname" : "nosqlfans18" }
{ "_id" : ObjectId("4ff2ae6816df1d1b33bad094"), "uid" : 19, "uname" : "nosqlfans19" }
has more
mongos> db.fans.ensureIndex({"uid":1})
mongos> db.fans.find({uid:10}).explain()
{
    "cursor" : "BtreeCursor uid_1",
    "nscanned" : 1,
    "nscannedObjects" : 1,
    "n" : 1,
    "millis" : 25,
    "nYields" : 0,
    "nChunkSkips" : 0,
    "isMultiKey" : false,
    "indexOnly" : false,
    "indexBounds" : {
        "uid" : [
            [
                10,
                10
            ]
        ]
    }
}

3.Collecton分片

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 : "",key : }); 

 

mongos> use admin
switched to db admin
mongos> db.runCommand({shardcollection : "nosql.fans",key : {uid:1}})
{ "collectionsharded" : "nosql.fans", "ok" : 1 }

PS: 

1). 操作必须切换到admin数据库下

2). 分片的collection系统要创建好索引

3). 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

 

4.查看分片状态

 

mongos> use nosql
mongos> db.fans.stats()
{
    "sharded" : true,
    "flags" : 1,
    "ns" : "nosql.fans",
    "count" : 100,
    "numExtents" : 2,
    "size" : 5968,
    "storageSize" : 20480,
    "totalIndexSize" : 24528,
    "indexSizes" : {
        "_id_" : 8176,
        "uid0_1" : 8176,
        "uid_1" : 8176
    },
    "avgObjSize" : 59.68,
    "nindexes" : 3,
    "nchunks" : 1,
    "shards" : {
        "shard1" : {
            "ns" : "nosql.test",
            "count" : 100,
            "size" : 5968,
            "avgObjSize" : 59.68,
            "storageSize" : 20480,
            "numExtents" : 2,
            "nindexes" : 3,
            "lastExtentSize" : 16384,
            "paddingFactor" : 1,
            "flags" : 1,
            "totalIndexSize" : 24528,
            "indexSizes" : {
                "_id_" : 8176,
                "uid0_1" : 8176,
                "uid_1" : 8176
            },
            "ok" : 1
        }
    },
    "ok" : 1
}
mongos>

再插入比较多的数据：

mongos> use nosql
switched to db nosql
mongos> for(var i=200;i<200003;i++)db.fans.save({uid:i,uname:'nosqlfans'+i});
mongos> db.fans.stats()
{
    "sharded" : true,
    "flags" : 1,
    "ns" : "nosql.fans",
    "count" : 200002,
    "numExtents" : 12,
    "size" : 12760184,
    "storageSize" : 22646784,
    "totalIndexSize" : 12116832,
    "indexSizes" : {
        "_id_" : 6508096,
        "uid_1" : 5608736
    },
    "avgObjSize" : 63.80028199718003,
    "nindexes" : 2,
    "nchunks" : 10,
    "shards" : {
        "shard1" : {
            "ns" : "nosql.fans",
            "count" : 9554,
            "size" : 573260,
            "avgObjSize" : 60.00209336403601,
            "storageSize" : 1396736,
            "numExtents" : 5,
            "nindexes" : 2,
            "lastExtentSize" : 1048576,
            "paddingFactor" : 1,
            "flags" : 1,
            "totalIndexSize" : 596848,
            "indexSizes" : {
                "_id_" : 318864,
                "uid_1" : 277984
            },
            "ok" : 1
        },
        "shard2" : {
            "ns" : "nosql.fans",
            "count" : 190448,
            "size" : 12186924,
            "avgObjSize" : 63.990821641602956,
            "storageSize" : 21250048,
            "numExtents" : 7,
            "nindexes" : 2,
            "lastExtentSize" : 10067968,
            "paddingFactor" : 1,
            "flags" : 1,
            "totalIndexSize" : 11519984,
            "indexSizes" : {
                "_id_" : 6189232,
                "uid_1" : 5330752
            },
            "ok" : 1
        }
    },
    "ok" : 1
}
mongos>

当再次插入大量数据时。。自动分片处理了！！所以OK！！！

 

八.停止所有服务脚本

[root@mon1 sh]# cat /opt/mongodb/sh/stop.sh
#!/bin/sh
check=`ps aux|grep mongo|grep configdb|awk '{print $2;}'|wc -l`
echo $check
while [ $check -gt 0 ]
do
       # echo $check
        no=`ps aux|grep mongo|grep configdb|awk '{print $2;}'|sed -n '1p'`
        kill -3 $no
        echo "kill $no mongo daemon is ok."
        sleep 2
        check=`ps aux|grep mongo|grep configdb|awk '{print $2;}'|wc -l`
        echo "stopping mongo,pls waiting..."
done

check=`ps aux|grep mongo|grep configsvr|awk '{print $2;}'|wc -l`
echo $check
while [ $check -gt 0 ]
do
       # echo $check
        no=`ps aux|grep mongo|grep configsvr|awk '{print $2;}'|sed -n '1p'`
        kill -3 $no
        echo "kill $no mongo daemon is ok."
        sleep 2
        check=`ps aux|grep mongo|grep configsvr|awk '{print $2;}'|wc -l`
        echo "stopping mongo,pls waiting..."
done

check=`ps aux|grep mongo|grep shardsvr|awk '{print $2;}'|wc -l`
echo $check
while [ $check -gt 0 ]
do
       # echo $check
        no=`ps aux|grep mongo|grep shardsvr|awk '{print $2;}'|sed -n '1p'`
        kill -3 $no
        echo "kill $no mongo daemon is ok."
        sleep 2
        check=`ps aux|grep mongo|grep shardsvr|awk '{print $2;}'|wc -l`
        echo "stopping mongo,pls waiting..."
done

echo "all mongodb stopped!"

九.分片管理

1.listshards:列出所有的Shard 

>use admin
>db.runCommand({listshards:1})

2.移除shard 

>use admin
>db.runCommand( { removeshard : "shard1/192.168.8.30:27021,192.168.8.31:27021" } )
>db.runCommand( { removeshard : "shard2/192.168.8.30:27022,192.168.8.31:27022" } )

对于移除的分片后，我们再加入相同分片时，会加不进去，可以按如下方法进行： 

mongos> use config
switched to db config
mongos> show collections
changelog
chunks
collections
databases
lockpings
locks
mongos
settings
shards
system.indexes
version
mongos> db.shards.find()
{ "_id" : "shard1", "host" : "shard1/192.168.8.30:27021,192.168.8.31:27021,192.168.8.32:27021", "maxSize" : NumberLong(20480) }
{ "_id" : "shard2", "host" : "shard2/192.168.8.30:27022,192.168.8.31:27022,192.168.8.32:27022", "maxSize" : NumberLong(20480) }

 要做的就是删除shards表中的信息，把移除的shard键值删除掉！再重新加入shard

如：db.shards.remove({"_id":"shard2"})

 

3.查看Sharding信息

> printShardingStatus()

 

PRIMARY> db.system.replset.find()

PRIMARY> rs.isMaster()