MongoDB分布式集群分片

MongoDB高可用集群搭建

一、环境准备

# 启动时需要使用非root用户，所有创建一个mongo用户：
useradd mongo

# 为mongo用户添加密码：
echo 123456 | passwd --stdin mongo

# 将mongo添加到sudoers
echo "mongo ALL = (root) NOPASSWD:ALL" | tee /etc/sudoers.d/mongo
chmod 0440 /etc/sudoers.d/mongo
#解决sudo: sorry, you must have a tty to run sudo问题，在/etc/sudoer注释掉 Default requiretty 一行
sudo sed -i 's/Defaults    requiretty/Defaults:chiansun !requiretty/' /etc/sudoers

# 创建一个mongo目录
mkdir /mongo

# 给相应的目录添加权限
chown -R mongo:mongo /mongo

# 配置mongo的yum源
cat >> /etc/yum.repos.d/mongodb-org-4.0.repo << EOF
[mongodb-org-4.0]
name=MongoDB Repository
baseurl=http://repo.mongodb.org/yum/redhat/\$releasever/mongodb-org/4.0/x86_64/
gpgcheck=1
enabled=1
gpgkey=https://www.mongodb.org/static/pgp/server-4.0.asc
EOF

# 关闭selinux
sed -i 's/SELINUX=enforcing/SELINUX=disabled/' /etc/selinux/config
setenforce 0

# 关闭防火墙
systemctl disable firewalld
systemctl stop firewalld

二、主机规划

192.168.33.14   node-1
192.168.33.15   node-2
192.168.33.16   node-3

node-1    node-2       node-3 
mongos    mongos       mongos     路由服务器，寻址
config    config       config     配置服务器，保存配置
shard1主  shard2主     shard3主    分片：保存数据
shard2从  shard3从     shard1从    副本集：备份数据，可以配置读写分离（主负责写，从负责同步数据和读）
shard3从  shard1从     shard2从

三、安装部署

# 分别在多台机器上使用mongo用户登录
sudo yum install -y mongodb-org 

# 分别在多台机器上创建mongo config server对应的目录
mkdir -p /mongo/config/{log,data,run}

# 分别在多台机器上修改config server的配置文件
cat > /mongo/config/mongod.conf << EOF
systemLog:
  destination: file
  logAppend: true
  path: /mongo/config/log/mongod.log
storage:
  dbPath: /mongo/config/data
  journal:
    enabled: true
processManagement:
  fork: true
  pidFilePath: /mongo/config/run/mongod.pid
net:
  port: 27100
  bindIp: 0.0.0.0
replication:
  replSetName: config
sharding:
  clusterRole: configsvr
EOF

# 启动所有的mongo config server服务
mongod --config /mongo/config/mongod.conf

# 登录任意一台配置服务器，初始化配置副本集
mongo --port 27100

# 创建配置
# id名要和replSetName名保持一致
config = {
   _id : "config",
    members : [
        {_id : 0, host : "192.168.33.14:27100" },
        {_id : 1, host : "192.168.33.15:27100" },
        {_id : 2, host : "192.168.33.16:27100" }
    ]
}

# 初始化副本集配置
rs.initiate(config)

# 查看分区状态
rs.status()

# 注意:其中，"_id" : "config"应与配置文件中配置的 replicaction.replSetName 一致，"members" 中的 "host" 为三个节点的ip和port

1.配置第一个分片和副本集

# 修改mongo shard1 server的配置文件
mkdir -p /mongo/shard1/{log,data,run}

# 分别在多台机器上修改shard1 server的配置文件
cat > /mongo/shard1/mongod.conf << EOF
systemLog:
  destination: file
  logAppend: true
  path: /mongo/shard1/log/mongod.log
storage:
  dbPath: /mongo/shard1/data
  journal:
    enabled: true
processManagement:
  fork: true
  pidFilePath: /mongo/shard1/run/mongod.pid
net:
  port: 27001
  bindIp: 0.0.0.0
replication:
  replSetName: shard1
sharding:
  clusterRole: shardsvr
EOF

# 启动所有的shard1 server
mongod --config /mongo/shard1/mongod.conf

# 登陆任意一台shard1服务器，初始化副本集
mongo --port 27001

# 使用admin数据库
use admin

# 定义副本集配置
config = {
   _id : "shard1",
    members : [
        {_id : 0, host : "192.168.33.14:27001" },
        {_id : 1, host : "192.168.33.15:27001" },
        {_id : 2, host : "192.168.33.16:27001" }
    ]
}

# 初始化副本集配置
rs.initiate(config);

# 查看分区状态
rs.status()

2.配置第二个分片和副本集

# 修改mongo shard2 server的配置文件
mkdir -p /mongo/shard2/{log,data,run}

# 分别在多台机器上修改shard2 server的配置文件
cat > /mongo/shard2/mongod.conf << EOF
systemLog:
  destination: file
  logAppend: true
  path: /mongo/shard2/log/mongod.log
storage:
  dbPath: /mongo/shard2/data
  journal:
    enabled: true
processManagement:
  fork: true
  pidFilePath: /mongo/shard2/run/mongod.pid
net:
  port: 27002
  bindIp: 0.0.0.0
replication:
  replSetName: shard2
sharding:
  clusterRole: shardsvr
EOF

# 启动所有的shard2 server
mongod --config /mongo/shard2/mongod.conf

# 登陆任意一台shard2服务器，初始化副本集
mongo --port 27002

# 使用admin数据库
use admin

# 定义副本集配置
config = {
   _id : "shard2",
    members : [
        {_id : 0, host : "192.168.33.14:27002" },
        {_id : 1, host : "192.168.33.15:27002" },
        {_id : 2, host : "192.168.33.16:27002" }
    ]
}

# 初始化副本集配置
rs.initiate(config)

# 查看分区状态
rs.status()

3.配置第三个分片和副本集

# 修改mongo shard3 server的配置文件
mkdir -p /mongo/shard3/{log,data,run}

# 分别在多台机器上修改shard3 server的配置文件
cat > /mongo/shard3/mongod.conf << EOF
systemLog:
  destination: file
  logAppend: true
  path: /mongo/shard3/log/mongod.log
storage:
  dbPath: /mongo/shard3/data
  journal:
    enabled: true
processManagement:
  fork: true
  pidFilePath: /mongo/shard3/run/mongod.pid
net:
  port: 27003
  bindIp: 0.0.0.0
replication:
  replSetName: shard3
sharding:
  clusterRole: shardsvr
EOF

# 启动所有的shard3 server
mongod --config /mongo/shard3/mongod.conf

# 登陆任意一台的shard3服务器，初始化副本集
mongo --port 27003

# 使用admin数据库
use admin

# 定义副本集配置
config = {
   _id : "shard3",
    members : [
        {_id : 0, host : "192.168.33.14:27003" },
        {_id : 1, host : "192.168.33.15:27003" },
        {_id : 2, host : "192.168.33.16:27003" }
    ]
}

# 初始化副本集配置
rs.initiate(config)

# 查看分区状态
rs.status()

4.配置mongos路由器

##### 注意：启动mongos是守候进程是因为/mongo/mongos/mongod.conf缺少了fork: true这个配置#######
------------------------------------------------------------------------------------------

mkdir -p /mongo/mongos/{log,data,run}

# 添加mongs的配置文件
cat > /mongo/mongos/mongod.conf << EOF
systemLog:
  destination: file
  logAppend: true
  path: /mongo/mongos/log/mongod.log
processManagement:
  fork: true
  pidFilePath: /mongo/mongos/run/mongod.pid
net:
  port: 27200
  bindIp: 0.0.0.0
sharding:
  configDB: config/192.168.33.14:27100,192.168.33.15:27100,192.168.33.16:27100
EOF

# 注意，这里configDB后面的config要与配置服务器的_id保持一致

# 启动路由服务器
mongos --config /mongo/mongos/mongod.conf

# 登录其中的一台路由节点，手动启用分片
mongo --port 27200

# 添加分片到mongos
sh.addShard("shard1/192.168.33.14:27001,192.168.33.15:27001,192.168.33.16:27001")
sh.addShard("shard2/192.168.33.15:27002,192.168.33.16:27002,192.168.33.14:27002")
sh.addShard("shard3/192.168.33.16:27003,192.168.33.14:27003,192.168.33.15:27003")

# 设置slave可读
rs.slaveOk()

5.常用操作

#没有分片是因为没有开启分片规则

# 对bike这个数据库开启分片功能
use admin
db.runCommand({"enablesharding":"bike"}) 

# 对bike数据库下的users集合按id的hash进行分片
db.runCommand({"shardcollection":"bike.users","key":{_id:'hashed'}})

# 启动所有的config server
mongod --config /mongo/config/mongod.conf

# 启动所有的shard1
mongod --config /mongo/shard1/mongod.conf

# 启动所有的shard2
mongod --config /mongo/shard2/mongod.conf

# 启动所有的shard3
mongod --config /mongo/shard3/mongod.conf

# 启动所有的mongos
mongos --config /mongo/mongos/mongod.conf

# 关闭服务
mongod --shutdown --dbpath /mongo/shard3/data
mongod --shutdown --dbpath /mongo/shard2/data
mongod --shutdown --dbpath /mongo/shard1/data
mongod --shutdown --dbpath /mongo/config/data