mongodb 4.0副本集搭建

时间 2020-08-08

原文原文链接

近期有同窗问mongodb副本集难不难部署，个人回答是不难，很快，几分钟搞定，比mysql MHA简单的不止一点半点。那么到底如何部署呢？请看下文。mysql

1. 准备工做

1.1 下载软件

选择版本并下载mongodb的软件，注意操做系统版本等。本次我选用的是percona分支的mongodb 4.2.8版本搭建，操做系统为centos6sql

cd /usr/local/
wget  https://www.percona.com/downloads/percona-server-mongodb-LATEST/percona-server-mongodb-4.2.8-8/binary/tarball/percona-server-mongodb-4.2.8-8-centos6-x86_64.tar.gz
tar -zxvf  percona-server-mongodb-4.2.8-8-centos6-x86_64.tar.gz
ln -s percona-server-mongodb-4.2.8-8 mongodb

1.2 规划各节点角色

各节点角色以下mongodb

IP	port	role
192.168.128.208	27017	PRIMARY
192.168.128.209	27017	SECONDARY
192.168.128.209	28017	ARBITER

2 部署

2.1 建立各节点相关目录

[root@m1 ~]# mkdir -p /data/mongodb/27017/{data,logs,tmp,etc,keyfile}
[root@m1 ~]# cd /data/mongodb/27017/
[root@m1 27017]# ll
总用量 20
drwxr-xr-x 2 root root 4096 8月   7 16:59 data
drwxr-xr-x 2 root root 4096 8月   7 16:59 etc
drwxr-xr-x 2 root root 4096 8月   7 16:59 keyfile
drwxr-xr-x 2 root root 4096 8月   7 16:59 logs
drwxr-xr-x 2 root root 4096 8月   7 16:59 tmp

2.2 配置文件

建立配置文件，并添加对应的配置信息，注意仲裁节点的端口vim

[root@m1 27017]# cd  /data/mongodb/27017/etc/
[root@m1 etc]# vim mongod.conf
添加以下内容

storage:
  dbPath: /data/mongodb/27017/data
  journal:
    enabled: true
systemLog:
  destination: file
  logAppend: true
  path: /data/mongodb/27017/logs/mongod.log
processManagement:
  fork: true
  pidFilePath: /data/mongodb/27017/tmp/mongod.pid
net:
  port: 27017
  bindIp: 0.0.0.0
replication:
  replSetName: "test1"                 # 副本集名称

2.3 启动各节点

以其中一个节点为例，其余节点修改对应配置文件便可centos

[root@m1 local]#  /usr/local/mongodb/bin/mongod   -f /data/mongodb/27017/etc/mongod.conf 
about to fork child process, waiting until server is ready for connections.
forked process: 30019
child process started successfully, parent exiting

2.4 初始化副本集

初始化副本集，指定各节点id及角色，注意副本集的名称和配置文件里一致。安全

在任意节点执行以下语句微信

> use admin
switched to db admin
> rs.initiate( {
... _id: "test1",
... members: [
... { _id: 0, host: "192.168.128.208:27017" },
... { _id: 1, host: "192.168.128.209:27017" },
... { _id: 2, host: "192.168.128.209:28017",arbiterOnly:true }
... ] })
{
    "ok" : 1,
    "$clusterTime" : {
        "clusterTime" : Timestamp(1596792682, 1),
        "signature" : {
            "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
            "keyId" : NumberLong(0)
        }
    },
    "operationTime" : Timestamp(1596792682, 1)
}

完成后能够查看各集群状态,以下，可见当前192.168.128.208:27017 为PRIMARY节点app

test1:PRIMARY> rs.status()
{
    "set" : "test1",
    "date" : ISODate("2020-08-07T11:09:24.454Z"),
    "myState" : 1,
    "term" : NumberLong(1),
    "syncingTo" : "",
    "syncSourceHost" : "",
    "syncSourceId" : -1,
    "heartbeatIntervalMillis" : NumberLong(2000),
    "majorityVoteCount" : 2,
    "writeMajorityCount" : 2,
    "optimes" : {
        "lastCommittedOpTime" : {
            "ts" : Timestamp(1596798563, 1),
            "t" : NumberLong(1)
        },
        "lastCommittedWallTime" : ISODate("2020-08-07T11:09:23.663Z"),
        "readConcernMajorityOpTime" : {
            "ts" : Timestamp(1596798563, 1),
            "t" : NumberLong(1)
        },
        "readConcernMajorityWallTime" : ISODate("2020-08-07T11:09:23.663Z"),
        "appliedOpTime" : {
            "ts" : Timestamp(1596798563, 1),
            "t" : NumberLong(1)
        },
        "durableOpTime" : {
            "ts" : Timestamp(1596798563, 1),
            "t" : NumberLong(1)
        },
        "lastAppliedWallTime" : ISODate("2020-08-07T11:09:23.663Z"),
        "lastDurableWallTime" : ISODate("2020-08-07T11:09:23.663Z")
    },
    "lastStableRecoveryTimestamp" : Timestamp(1596798513, 1),
    "lastStableCheckpointTimestamp" : Timestamp(1596798513, 1),
    "electionCandidateMetrics" : {
        "lastElectionReason" : "electionTimeout",
        "lastElectionDate" : ISODate("2020-08-07T09:31:33.409Z"),
        "electionTerm" : NumberLong(1),
        "lastCommittedOpTimeAtElection" : {
            "ts" : Timestamp(0, 0),
            "t" : NumberLong(-1)
        },
        "lastSeenOpTimeAtElection" : {
            "ts" : Timestamp(1596792682, 1),
            "t" : NumberLong(-1)
        },
        "numVotesNeeded" : 2,
        "priorityAtElection" : 1,
        "electionTimeoutMillis" : NumberLong(10000),
        "numCatchUpOps" : NumberLong(0),
        "newTermStartDate" : ISODate("2020-08-07T09:31:33.444Z"),
        "wMajorityWriteAvailabilityDate" : ISODate("2020-08-07T09:31:34.050Z")
    },
    "members" : [
        {
            "_id" : 0,
            "name" : "192.168.128.208:27017",
            "health" : 1,
            "state" : 1,
            "stateStr" : "PRIMARY",
            "uptime" : 5950,
            "optime" : {
                "ts" : Timestamp(1596798563, 1),
                "t" : NumberLong(1)
            },
            "optimeDate" : ISODate("2020-08-07T11:09:23Z"),
            "syncingTo" : "",
            "syncSourceHost" : "",
            "syncSourceId" : -1,
            "infoMessage" : "",
            "electionTime" : Timestamp(1596792693, 1),
            "electionDate" : ISODate("2020-08-07T09:31:33Z"),
            "configVersion" : 1,
            "self" : true,
            "lastHeartbeatMessage" : ""
        },
        {
            "_id" : 1,
            "name" : "192.168.128.209:27017",
            "health" : 1,
            "state" : 2,
            "stateStr" : "SECONDARY",
            "uptime" : 5882,
            "optime" : {
                "ts" : Timestamp(1596798563, 1),
                "t" : NumberLong(1)
            },
            "optimeDurable" : {
                "ts" : Timestamp(1596798563, 1),
                "t" : NumberLong(1)
            },
            "optimeDate" : ISODate("2020-08-07T11:09:23Z"),
            "optimeDurableDate" : ISODate("2020-08-07T11:09:23Z"),
            "lastHeartbeat" : ISODate("2020-08-07T11:09:23.672Z"),
            "lastHeartbeatRecv" : ISODate("2020-08-07T11:09:22.804Z"),
            "pingMs" : NumberLong(0),
            "lastHeartbeatMessage" : "",
            "syncingTo" : "192.168.128.208:27017",
            "syncSourceHost" : "192.168.128.208:27017",
            "syncSourceId" : 0,
            "infoMessage" : "",
            "configVersion" : 1
        },
        {
            "_id" : 2,
            "name" : "192.168.128.209:28017",
            "health" : 1,
            "state" : 7,
            "stateStr" : "ARBITER",
            "uptime" : 5882,
            "lastHeartbeat" : ISODate("2020-08-07T11:09:23.672Z"),
            "lastHeartbeatRecv" : ISODate("2020-08-07T11:09:22.952Z"),
            "pingMs" : NumberLong(0),
            "lastHeartbeatMessage" : "",
            "syncingTo" : "",
            "syncSourceHost" : "",
            "syncSourceId" : -1,
            "infoMessage" : "",
            "configVersion" : 1
        }
    ],
    "ok" : 1,
    "$clusterTime" : {
        "clusterTime" : Timestamp(1596798563, 1),
        "signature" : {
            "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
            "keyId" : NumberLong(0)
        }
    },
    "operationTime" : Timestamp(1596798563, 1)
}
test1:PRIMARY>

3 修改成认证模式

为考虑安全性等，须要开启认证模式（须要经过用户名/密码方式登陆）spa

3.1 建立用户

建立超级管理员帐号

test1:PRIMARY> db.createUser({user: "root", pwd: "Root#123", roles: [{role: "root", db: "admin"}]})
Successfully added user: {
    "user" : "root",
    "roles" : [
        {
            "role" : "root",
            "db" : "admin"
        }
    ]
}

3.2 建立key文件

在主库上执行脚本生成key文件，而后将结拷贝到另外2个节点

[root@m1 mongodb]# cd /data/mongodb/27017/keyfile/
[root@m1 keyfile]# openssl rand -base64 756 > mongo.key
[root@m1 keyfile]# chmod 600 mongo.key   # 必须修改成600权限，不然没法启动

以上完成后，将文件复制到另外2个节点

3.3 修改配置文件

配置文件中 添加以下内容，注意不一样节点的文件路径

security:
  authorization: enabled
  clusterAuthMode: keyFile
  keyFile: /data/mongodb/27017/keyfile/mongo.key

3.4 重启后并用认证模式登录

# 关闭mongodb
[root@m1 keyfile]#  /usr/local/mongodb/bin/mongod   -f /data/mongodb/27017/etc/mongod.conf  -shutdown
killing process with pid: 30675
# 启动mongodb
[root@m1 keyfile]#  /usr/local/mongodb/bin/mongod   -f /data/mongodb/27017/etc/mongod.conf about to fork child process, waiting until server is ready for connections.
forked process: 2430

child process started successfully, parent exiting

#  认证模式登录
[root@m1 keyfile]# 
[root@m1 keyfile]# /usr/local/mongodb/bin/mongo   -u root  -p 'Root#123'  --authenticationDatabase admin

至此，mongodb 副本集搭建完毕，你会了吗？

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