1 MongoDB 分片(高可用)
1.1 准备工作
- 三台虚拟机
- 安装MongoDB
- 虚拟机相互之间可以相互通信
- 虚拟机与主机之间可以相互通信
1.2 安装MongoDB
在Ubuntu16.04 中安装 MongoDB 。参考步骤MongoDB官方网站
-
安装时会报错
E: The method driver /usr/lib/apt/methods/https could not be found. N: Is the package apt-transport-https installed?
提示需要安装apt-transport-https
sudo apt-get install -y apt-transport-https
1.3 启动MongoDB
sudo service mongod start
检查是否启动成功
sudo cat /var/log/mongodb/mongod.log
2019-04-19T15:40:52.808+0800 I NETWORK [initandlisten] waiting for connections on port 27017
2 MongoDB 分片
分片(sharding)是将数据拆分,将其分散存到不同机器上的过程。MongoDB 支持自动分片,可以使数据库架构对应用程序不可见。对于应用程序来说,好像始终在使用一个单机的 MongoDB 服务器一样,另一方面,MongoDB 自动处理数据在分片上的分布,也更容易添加和删除分片。类似于mysql中的分库。
2.1 基础组件
其利用到了四个组件:mongos,config server,shard,replica set
mongos:数据库集群请求的入口,所有请求需要经过mongos进行协调,无需在应用层面利用程序来进行路由选择,mongos其自身是一个请求分发中心,负责将外部的请求分发到对应的shard服务器上,mongos作为统一的请求入口,为防止mongos单节点故障,一般需要对其做HA。可以理解为在微服务架构中的路由Eureka。
config server:配置服务器,存储所有数据库元数据(分片,路由)的配置。mongos本身没有物理存储分片服务器和数据路由信息,只是存缓存在内存中来读取数据,mongos在第一次启动或后期重启时候,就会从config server中加载配置信息,如果配置服务器信息发生更新会通知所有的mongos来更新自己的状态,从而保证准确的请求路由,生产环境中通常也需要多个config server,防止配置文件存在单节点丢失问题。理解为 配置中心
shard:在传统意义上来讲,如果存在海量数据,单台服务器存储1T压力非常大,无论考虑数据库的硬盘,网络IO,又有CPU,内存的瓶颈,如果多台进行分摊1T的数据,到每台上就是可估量的较小数据,在mongodb集群只要设置好分片规则,通过mongos操作数据库,就可以自动把对应的操作请求转发到对应的后端分片服务器上。真正的存储
replica set:在总体mongodb集群架构中,对应的分片节点,如果单台机器下线,对应整个集群的数据就会出现部分缺失,这是不能发生的,因此对于shard节点需要replica set来保证数据的可靠性,生产环境通常为2个副本+1个仲裁。 副本保持数据的HA
2.2 架构图
3 安装部署
为了节省服务器,采用多实例配置,三个mongos,三个config server,单个服务器上面运行不通角色的shard(为了后期数据分片均匀,将三台shard在各个服务器上充当不同的角色。),在一个节点内采用replica set保证高可用,对应主机与端口信息如下:
主机名 | IP地址 | 组件mongos | 组件config server | shard |
---|---|---|---|---|
主节点: 22001 | ||||
mongodb-1 | 192.168.90.130 | 端口:20000 | 端口:21000 | 副本节点:22002 |
仲裁节点:22003 | ||||
主节点: 22002 | ||||
mongodb-2 | 192.168.90.131 | 端口:20000 | 端口:21000 | 副本节点:22001 |
仲裁节点:22003 | ||||
主节点: 22003 | ||||
mongodb-3 | 192.168.90.132 | 端口:20000 | 端口:21000 | 副本节点:22001 |
仲裁节点:22002 |
3.1 部署配置服务器集群
3.1.1 先创建对应的文件夹
mkdir -p /usr/local/mongo/mongoconf/{data,log,config}
touch mongoconfg.conf
touch mongoconf.log
3.1.2 填写对应的配置文件
# mongod.conf
# for documentation of all options, see:
# http://docs.mongodb.org/manual/reference/configuration-options/
# Where and how to store data.
storage:
dbPath: /usr/local/mongo/mongoconf/data
journal:
enabled: true
commitIntervalMs: 200
# engine:
# mmapv1:
# wiredTiger:
# where to write logging data.
systemLog:
destination: file
logAppend: true
path: /usr/local/mongo/mongoconf/log/mongoconf.log
# network interfaces
net:
port: 21000
bindIp: 0.0.0.0
maxIncomingConnections: 1000
# how the process runs
processManagement:
fork: true
#security:
#operationProfiling:
#replication:
replication:
replSetName: replconf
#sharding:
sharding:
clusterRole: configsvr
## Enterprise-Only Options:
#auditLog:
#snmp:
配置集群需要指定 data ,log ,以及对应的sharding角色
3.1.3 启动config集群
在三台机器上都配置好对应的文件后可以启动config集群
mogod -f /usr/local/mongo/mongoconf/conf/mongoconf.conf
3.1.4 副本初始化操作
进入任意一台机器(130为例),做集群副本初始化操作
mongo 192.168.90.130
config = {
_id:"replconf"
members:[
{_id:0,host:"192.168.90.130:21000"}
{_id:0,host:"192.168.90.131:21000"}
{_id:0,host:"192.168.90.132:21000"}
]
}
rs.initiate(config)
//查看集群状态
rs.status()
返回结果如下
{
"set" : "replconf",
"date" : ISODate("2019-04-21T06:38:50.164Z"),
"myState" : 2,
"term" : NumberLong(3),
"syncingTo" : "192.168.90.131:21000",
"syncSourceHost" : "192.168.90.131:21000",
...
"members" : [
{
"_id" : 0,
"name" : "192.168.90.130:21000",
"health" : 1,
"state" : 2,
"stateStr" : "SECONDARY",
"uptime" : 305,
"optime" : {
"ts" : Timestamp(1555828718, 1),
"t" : NumberLong(3)
},
"optimeDurable" : {
"ts" : Timestamp(1555828718, 1),
"t" : NumberLong(3)
},
"optimeDate" : ISODate("2019-04-21T06:38:38Z"),
"optimeDurableDate" : ISODate("2019-04-21T06:38:38Z"),
"lastHeartbeat" : ISODate("2019-04-21T06:38:49.409Z"),
"lastHeartbeatRecv" : ISODate("2019-04-21T06:38:49.408Z"),
"pingMs" : NumberLong(0),
"lastHeartbeatMessage" : "",
"syncingTo" : "192.168.90.131:21000",
"syncSourceHost" : "192.168.90.131:21000",
"syncSourceId" : 1,
"infoMessage" : "",
"configVersion" : 1
},
{
"_id" : 1,
"name" : "192.168.90.131:21000",
"health" : 1,
"state" : 1,
"stateStr" : "PRIMARY",
"uptime" : 307,
"optime" : {
"ts" : Timestamp(1555828718, 1),
"t" : NumberLong(3)
},
"optimeDurable" : {
"ts" : Timestamp(1555828718, 1),
"t" : NumberLong(3)
},
"optimeDate" : ISODate("2019-04-21T06:38:38Z"),
"optimeDurableDate" : ISODate("2019-04-21T06:38:38Z"),
"lastHeartbeat" : ISODate("2019-04-21T06:38:49.380Z"),
"lastHeartbeatRecv" : ISODate("2019-04-21T06:38:49.635Z"),
"pingMs" : NumberLong(0),
"lastHeartbeatMessage" : "",
"syncingTo" : "",
"syncSourceHost" : "",
"syncSourceId" : -1,
"infoMessage" : "",
"electionTime" : Timestamp(1555828429, 1),
"electionDate" : ISODate("2019-04-21T06:33:49Z"),
"configVersion" : 1
},
{
"_id" : 2,
"name" : "192.168.90.132:21000",
"health" : 1,
"state" : 2,
"stateStr" : "SECONDARY",
"uptime" : 319,
"optime" : {
"ts" : Timestamp(1555828718, 1),
"t" : NumberLong(3)
},
"optimeDate" : ISODate("2019-04-21T06:38:38Z"),
"syncingTo" : "192.168.90.131:21000",
"syncSourceHost" : "192.168.90.131:21000",
"syncSourceId" : 1,
"infoMessage" : "",
"configVersion" : 1,
"self" : true,
"lastHeartbeatMessage" : ""
}
],
"ok" : 1,
...
}
可以看出config集群部署成功,且通过选举机制选定131为primary节点。
3.2 部署Shard分片集群
3.2.1 分别对三片数据存储创建对应的文件夹
mkdir -p shard1/{data,conf,log}
mkdir -p shard2/{data,conf,log}
mkdir -p shard3/{data,conf,log}
touch shard1/log/shard1.log
touch shard2/log/shard2.log
touch shard3/log/shard3.log
3.2.2 创建对应的配置文件
# mongod.conf
# for documentation of all options, see:
# http://docs.mongodb.org/manual/reference/configuration-options/
# Where and how to store data.
storage:
dbPath: /usr/local/mongo/shard1/data
journal:
enabled: true
commitIntervalMs: 200
mmapv1:
smallFiles: true
# wiredTiger:
# where to write logging data.
systemLog:
destination: file
logAppend: true
path: /usr/local/mongo/shard1/log/shard1.log
# network interfaces
net:
port: 22001
bindIp: 0.0.0.0
maxIncomingConnections: 1000
# how the process runs
processManagement:
fork: true
#security:
#operationProfiling:
#replication:
replication:
replSetName: shard1
oplogSizeMB: 4096
#sharding:
sharding:
clusterRole: shardsvr
## Enterprise-Only Options:
#auditLog:
#snmp:
分别建立shard1,shard2,shard3 的配置文件
3.2.3 启动对应的shard
mongod -f /usr/local/mongo/shard1/conf/shard1.conf
mongod -f /usr/local/mongo/shard2/conf/shard2.conf
mongod -f /usr/local/mongo/shard3/conf/shard3.conf
使用
netstat -lntup
来查看进程
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:22001 0.0.0.0:* LISTEN 1891/mongod
tcp 0 0 0.0.0.0:22002 0.0.0.0:* LISTEN 1974/mongod
tcp 0 0 0.0.0.0:22003 0.0.0.0:* LISTEN 2026/mongod
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN -
tcp 0 0 127.0.0.1:6010 0.0.0.0:* LISTEN -
tcp 0 0 0.0.0.0:21000 0.0.0.0:* LISTEN 1779/mongod
发现进程全部启动
3.2.4 指定对应shard集群的副本
在130 上登录
mongo 192.168.90.130:22001
指定集群以及对应的arbiter节点
config = {
_id:"shard1",
members:[
{_id:0,host:"192.168.90.130:22001"},
{_id:1,host:"192.168.90.131:22001"},
{_id:2,host:"192.168.90.132:22001",arbiterOnly:true}
]
}
rs.initate(config)
rs.status()
在131,132 节点登录,哪一个节点初始化 即哪一个节点第一次优先作为primary节点
config = {
_id:"shard2",
members:[
{_id:0,host:"192.168.90.130:22002",arbiterOnly:true},
{_id:1,host:"192.168.90.131:22002"},
{_id:2,host:"192.168.90.132:22002"}
]
}
rs.initate(config)
rs.status()
config = {
_id:"shard3",
members:[
{_id:0,host:"192.168.90.130:22001"},
{_id:1,host:"192.168.90.131:22001",arbiterOnly:true},
{_id:2,host:"192.168.90.132:22001"}
]
}
rs.initate(config)
rs.status()
3.3 配置mongos路由集群
3.3.1 创建对应文件
mkdir -p ./mongos/{config,log}
因为mongos不需要存储数据或者元数据信息,只负责处理请求分发,当启动时到config集群中取得元数据信息加载到内存使用。
3.3.2 配置文件
# mongod.conf
# for documentation of all options, see:
# http://docs.mongodb.org/manual/reference/configuration-options/
# Where and how to store data.
# engine:
# mmapv1:
# wiredTiger:
# where to write logging data.
systemLog:
destination: file
logAppend: true
path: /usr/local/mongo/mongos/log/mongos.log
# network interfaces
net:
port: 20000
bindIp: 0.0.0.0
maxIncomingConnections: 1000
# how the process runs
processManagement:
fork: true
sharding:
configDB: replconf/mongo0:21000,mongo1:21000,mongo2:21000
## Enterprise-Only Options:
#auditLog:
3.3.3 启动mongos
mongos -f /usr/local/mongo/mongos/conf/mongos.conf
查看集群启动情况
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:22001 0.0.0.0:* LISTEN 1891/mongod
tcp 0 0 0.0.0.0:22002 0.0.0.0:* LISTEN 1974/mongod
tcp 0 0 0.0.0.0:22003 0.0.0.0:* LISTEN 2026/mongod
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN -
tcp 0 0 127.0.0.1:6010 0.0.0.0:* LISTEN -
tcp 0 0 0.0.0.0:20000 0.0.0.0:* LISTEN 2174/mongos
tcp 0 0 0.0.0.0:21000 0.0.0.0:* LISTEN 1779/mongod
3.3.4 在admin表中填写shard分片信息
登录任意一台mongos,在admin表中加入信息
use admin
db.runCommand(
{
addShard:"shard1/192.168.90.130:22001,192.168.90.131:22001,192.168.90.132:22001"
}
)
db.runCommand(
{
addShard:"shard2/192.168.90.130:22002,192.168.90.131:22002,192.168.90.132:22002"
}
)
db.runCommand(
{
addShard:"shard3/192.168.90.130:22003,192.168.90.131:22003,192.168.90.132:22003"
}
)
sh.status()
返回信息:
--- Sharding Status ---
sharding version: {
"_id" : 1,
"minCompatibleVersion" : 5,
"currentVersion" : 6,
"clusterId" : ObjectId("5cba82d33290d8f4fb3ac8f7")
}
shards:
{ "_id" : "shard1", "host" : "shard1/192.168.90.130:22001,192.168.90.132:22001", "state" : 1 }
{ "_id" : "shard2", "host" : "shard2/192.168.90.130:22002,192.168.90.131:22002", "state" : 1 }
{ "_id" : "shard3", "host" : "shard3/192.168.90.131:22003,192.168.90.132:22003", "state" : 1 }
active mongoses:
....
3.3.5 给对应的表进行分片
use admin
db.runCommand({
shardCollection:"lishubindb.table1",key:{_id:"hashed"}
})
db.runCommand({
listshards:1
})
3.4 测试
加入10W条数据到table1集合中
use lishubindb
for(var i=0;i<100000;i++){
db.table1.insert({
"name":"lishubin"+i,"num":i
})
}
观察分片情况
db.table1.status()
"ns" : "lishubindb.table1",
"count" : 100000,
"size" : 5888890,
"storageSize" : 2072576,
"totalIndexSize" : 4694016,
"indexSizes" : {
"_id_" : 1060864,
"_id_hashed" : 3633152
},
"avgObjSize" : 58,
"maxSize" : NumberLong(0),
"nindexes" : 2,
"nchunks" : 6,
"shards" : {
"shard3" : {
"ns" : "lishubindb.table1",
"size" : 1969256,
"count" : 33440,
"avgObjSize" : 58,
"storageSize" : 712704,
"capped" : false,
...
},
"shard2" : {
"ns" : "lishubindb.table1",
"size" : 1973048,
"count" : 33505,
"avgObjSize" : 58,
"storageSize" : 708608,
"capped" : false,
...
},
"shard1" : {
"ns" : "lishubindb.table1",
"size" : 1946586,
"count" : 33055,
"avgObjSize" : 58,
"storageSize" : 651264,
"capped" : false,
...
},