Mongo复制集部署

原创

两个小黄鹂 2023-03-10 14:55:52 ©著作权

文章标签 linux mongodb centos 数据库 sed 文章分类 HarmonyOS 后端开发

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连接Mongo集群，应用层面可以直接区分读写状态，无需其他应用做读写分离，架构设计如图所示：

Mongo复制集部署_数据库

1. 获取MongoDB

https://www.mongodb.com/try/download/community

2. 上传解压

cd /mongodb/
rz
rz waiting to receive.
Starting zmodem transfer.  Press Ctrl+C to cancel.
Transferring mongodb-linux-x86_64-rhel70-4.2.8.tgz...
  100%  129656 KB    32414 KB/sec    00:00:04       0 Errors  
tar xf  mongodb-linux-x86_64-rhel70-4.2.8.tgz

3. 关闭THP

echo 'echo never > /sys/kernel/mm/transparent_hugepage/defrag' >> /etc/rc.d/rc.local
echo 'echo never > /sys/kernel/mm/transparent_hugepage/enabled' >> /etc/rc.d/rc.local

修改 /etc/default/grub

GRUB_CMDLINE_LINUX="crashkernel=auto ipv6.disable=1 rd.lvm.lv=rhel/root rd.lvm.lv=rhel/swap rhgb quiet transparent_hugepage=never"

执行如下命令生效，有些系统不生效是因为没有选对相应的命令

EFI使用如下命令

grub2-mkconfig -o /boot/efi/EFI/redhat/grub.cfg

BIOS使用如下命令

grub2-mkconfig -o /boot/grub2/grub.cfg

修改完成重启机器

[root@mongo01~]# grep Huge /proc/meminfo
AnonHugePages:     83968 kB
HugePages_Total:       0  #success
HugePages_Free:        0
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       2048 kB
[root@mongo01~]# cat /proc/sys/vm/nr_hugepages
0  #success

4. 环境准备

创建所需用户和组

useradd mongo
passwd mongo

mkdir -p /mongodb/conf
mkdir -p /mongodb/log
mkdir -p /mongodb/data

修改权限

chown -R mongo:mongo /mongodb

切换用户并设置环境变量

su - mongo
vi .bash_profile
export PATH=/mongodb/app/bin:$PATH
source .bash_profile

5. 创建配置文件

bindIp以所在服务器为准

$ cat >> /mongodb/mongodb.yaml <<EOF
systemLog:
  destination: file
  path: /mongodb/log/mongod.log
  logAppend: true
processManagement:
  fork: true
  pidFilePath: /mongodb/mongodb.pid
storage:
  dbPath: /mongodb/data
  journal:
    enabled: true
net:
  bindIp: localhost,192.168.1.11
  port: 27017
security:
  keyFile: /mongodb/secret
  authorization: enabled
replication:
  replSetName: MongoRepl
EOF

6. 创建密码文件

三个节点需要配置相同的keyfile，否则复发互相通信，此处仅需生成一次，拷贝至其他服务器即可

$ openssl rand -base64 666 > /mongodb/secret
$ chmod 400 /mongodb/secret
$ scp /mongodb/secret mongo@192.168.62.22:/mongodb/secret
$ scp /mongodb/secret mongo@192.168.62.23:/mongodb/secret

7. 三个节点启动mongod进程

$ mongod -f /mongodb/mongodb.yaml
$ ps -ef | grep mongod

8. 初始化副本集

所有节点都执行rs.initiate

$ mongo
> rs.initiate()
{
        "info2" : "no configuration specified. Using a default configuration for the set",
        "me" : "192.168.1.11:27017",
        "ok" : 1,
        "operationTime" : Timestamp(1605262167, 1),
        "$clusterTime" : {
                "clusterTime" : Timestamp(1605262167, 1),
                "signature" : {
                        "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
                        "keyId" : NumberLong(0)
                }
        }
}

如下设置方式设置了权重

rs.initiate({_id:"MongoRepl",
  version:1,
  members:[{ _id:0, host:"192.168.1.11:27017",priority:2},
    { _id:1, host:"192.168.1.12:27017",priority:1},
    { _id:2, host:"192.168.1.13:27017",priority:1}
  ]}
)

设置一主一从一仲裁

```javascript
rs.initiate({_id:"MongoRepl",
  version:1,
  members:[{ _id:0, host:"192.168.1.11:27017",priority:2},
    { _id:1, host:"192.168.1.12:27017",priority:1},
    { _id:2, host:"192.168.1.13:27017","arbiterOnly":true}
  ]}
)

9. 添加数据库管理用户

$ mongo
MongoRepl:PRIMARY> use admin
MongoRepl:PRIMARY> db.createUser({user: "admin",pwd: "admin1234",roles:[{role: "root",db:"admin"}]})
Successfully added user: {
    "user" : "admin",
    "roles" : [
        {
            "role" : "root",
            "db" : "admin"
        }
    ]
}

10. 建立业务数据库及用户

mongo用户创建比较特殊，要想用户能直接登录对应的数据库，需要在创建用户前use数据库

$ mongo
MongoRepl:PRIMARY> use admin
MongoRepl:PRIMARY> db.auth("admin","admin1234")
MongoRepl:PRIMARY> use testdb
MongoRepl:PRIMARY> db.createUser({user: "test",pwd: "test1234",roles:[{role: "readWrite",db:"testdb"}]})
Successfully added user: {
    "user" : "test",
    "roles" : [
        {
            "role" : "readWrite",
            "db" : "testdb"
        }
    ]
}

11. 副本集验证

验证同步

登录主节点新增数据

$ mongo
MongoRepl:PRIMARY> use testdb
MongoRepl:PRIMARY> db.auth("test","test1234")
MongoRepl:PRIMARY> db.test.insert({"name":"test"})
WriteResult({ "nInserted" : 1 })
MongoRepl:PRIMARY> db.test.find()
{ "_id" : ObjectId("5ac9f5e06e02cf1ec5d82ae7"), "name" : "test" }

登录从节点192.168.1.12查询数据

$ mongo
MongoRepl:SECONDARY> use testdb
MongoRepl:SECONDARY> db.auth("test","test1234")
MongoRepl:SECONDARY> rs.slaveOk()
MongoRepl:SECONDARY> db.test.find()
{ "_id" : ObjectId("5ac9f5e06e02cf1ec5d82ae7"), "name" : "test" }

验证故障转移

关闭主节点

$ mongo
MongoRepl:PRIMARY> use admin
MongoRepl:PRIMARY> db.auth("admin","admin1234")
MongoRepl:PRIMARY> db.shutdownServer()
server should be down...
2018-04-09T09:50:30.195+0800 I NETWORK  [thread1] trying reconnect to 127.0.0.1:27017 (127.0.0.1) failed
2018-04-09T09:50:30.195+0800 W NETWORK  [thread1] Failed to connect to 127.0.0.1:27017, in(checking socket for error after poll), reason: Connection refused

确认主节点mongod进程已关闭

$ ps -ef|grep mongod
mongo      3799   1581  0 09:54 pts/0    00:00:00 grep mongod

登录从节点查看集群状态

$ mongo
MongoRepl:PRIMARY> db.auth("admin","admin1234")
1
MongoRepl:PRIMARY> rs.status()
{
        "set" : "MongoRepl",
        "date" : ISODate("2020-11-13T10:47:45.141Z"),
        "myState" : 1,
        "term" : NumberLong(2),
        "heartbeatIntervalMillis" : NumberLong(2000),
        "optimes" : {
                "lastCommittedOpTime" : {
                        "ts" : Timestamp(1605264400, 1),
                        "t" : NumberLong(1)
                },
                "readConcernMajorityOpTime" : {
                        "ts" : Timestamp(1605264400, 1),
                        "t" : NumberLong(1)
                },
                "appliedOpTime" : {
                        "ts" : Timestamp(1605264456, 1),
                        "t" : NumberLong(2)
                },
                "durableOpTime" : {
                        "ts" : Timestamp(1605264456, 1),
                        "t" : NumberLong(2)
                }
        },
        "members" : [
                {
                        "_id" : 0,
                        "name" : "192.168.1.11:27017",
                        "health" : 0,
                        "state" : 8,
                        "stateStr" : "(not reachable/healthy)",
                        "uptime" : 0,
                        "optime" : {
                                "ts" : Timestamp(0, 0),
                                "t" : NumberLong(-1)
                        },
                        "optimeDurable" : {
                                "ts" : Timestamp(0, 0),
                                "t" : NumberLong(-1)
                        },
                        "optimeDate" : ISODate("1970-01-01T00:00:00Z"),
                        "optimeDurableDate" : ISODate("1970-01-01T00:00:00Z"),
                        "lastHeartbeat" : ISODate("2020-11-13T10:47:43.243Z"),
                        "lastHeartbeatRecv" : ISODate("2020-11-13T10:46:45.196Z"),
                        "pingMs" : NumberLong(0),
                        "lastHeartbeatMessage" : "Connection refused",
                        "configVersion" : -1
                },
                {
                        "_id" : 1,
                        "name" : "192.168.1.12:27017",
                        "health" : 1,
                        "state" : 1,
                        "stateStr" : "PRIMARY",
                        "uptime" : 7748,
                        "optime" : {
                                "ts" : Timestamp(1605264456, 1),
                                "t" : NumberLong(2)
                        },
                        "optimeDate" : ISODate("2020-11-13T10:47:36Z"),
                        "infoMessage" : "could not find member to sync from",
                        "electionTime" : Timestamp(1605264415, 1),
                        "electionDate" : ISODate("2020-11-13T10:46:55Z"),
                        "configVersion" : 3,
                        "self" : true
                },
                {
                        "_id" : 2,
                        "name" : "192.168.1.13:27017",
                        "health" : 1,
                        "state" : 7,
                        "stateStr" : "ARBITER",
                        "uptime" : 1241,
                        "lastHeartbeat" : ISODate("2020-11-13T10:47:43.186Z"),
                        "lastHeartbeatRecv" : ISODate("2020-11-13T10:47:44.331Z"),
                        "pingMs" : NumberLong(0),
                        "configVersion" : 3
                }
        ],
        "ok" : 1,
        "operationTime" : Timestamp(1605264456, 1),
        "$clusterTime" : {
                "clusterTime" : Timestamp(1605264456, 1),
                "signature" : {
                        "hash" : BinData(0,"j7wJlWUpy/znoe6RSdnRL/yfVz0="),
                        "keyId" : NumberLong("6894548517361025025")
                }
        }
}