### **常见的复制集** 线上环境常见的架构为副本集，可以理解为一主多从。 #### 下图：1主2从  #### 下图：一主一从一仲裁  ### 服务器信息： 三台机器一样配置2核16G内存 存储盘100G > "host" : "10.1.1.159:27020" "host" : "10.1.1.77:27020" "host" : "10.1.1.178:27020 ### 1、我们在其中一台机器配置： [root@10-1-1-159 ~]# wget https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-rhel70-4.2.1.tgz [root@10-1-1-159 ~]# tar -zxvf mongodb-linux-x86_64-rhel70-4.2.1.tgz -C /data/ [root@10-1-1-159 ~]# mkdir /data/mongodb/{data,logs,pid,conf} -p 配置文件： ``` [root@10-1-1-159 ~]# cat /data/mongodb/conf/mongodb.conf systemLog: destination: file logAppend: true path: /data/mongodb/logs/mongod.log storage: dbPath: /data/mongodb/data journal: enabled: true directoryPerDB: true wiredTiger: engineConfig: cacheSizeGB: 8 #如果一台机器启动一个实例这个可以注释选择默认，如果一台机器启动多个实例，需要设置内存大小，避免互相抢占内存 directoryForIndexes: true processManagement: fork: true pidFilePath: /data/mongodb/pid/mongod.pid net: port: 27020 bindIp: 10.1.1.159,localhost #修改为本机IP地址 maxIncomingConnections: 5000 #security: #keyFile: /data/mongodb/conf/keyfile #authorization: enabled replication: # oplogSizeMB: 1024 replSetName: rs02 ``` ### 2、将配置负复制到其他机器： [root@10-1-1-159 ~]# scp -r /data/* root@10.1.1.77:/data/ [root@10-1-1-159 ~]# scp -r /data/* root@10.1.1.178:/data/ 目录结构： ``` [root@10-1-1-178 data]# tree mongodb mongodb ├── conf │   └── mongodb.conf ├── data ├── logs └── pid ``` ### 3、三台机器分别执行： >groupadd mongod useradd -g mongod mongod yum install -y libcurl openssl glibc cd /data ln -s mongodb-linux-x86_64-rhel70-4.2.1 mongodb-4.2 chown -R mongod.mongod /data sudo -u mongod /data/mongodb4.2.1/bin/mongod -f /data/mongodb/conf/mongodb.conf 配置复制集： #副本集名称rs02和配置文件中replSetName保持一致 >config = { _id:"rs02", members:[                      {_id:0,host:"10.1.1.159:27010",priority:90},                       {_id:1,host:"10.1.1.77:27010",priority:90},                      {_id:2,host:"10.1.1.178:27010",arbiterOnly:true}     ] } #初始化 >rs.initiate(config);  ### 4、在其中一台机器执行： ``` [root@10-1-1-159 ~]# /data/mongodb3.6.9/bin/mongo 10.1.1.159:27020 > use admin switched to db admin > config = { _id:"rs02", members:[ ...                      {_id:0,host:"10.1.1.159:27020",priority:90}, ...                      {_id:1,host:"10.1.1.77:27020",priority:90}, ...                     {_id:2,host:"10.1.1.178:27020",arbiterOnly:true} ...     ] ... } { "_id" : "rs02", "members" : [ { "_id" : 0, "host" : "10.1.1.159:27020", "priority" : 90 }, { "_id" : 1, "host" : "10.1.1.77:27020", "priority" : 90 }, { "_id" : 2, "host" : "10.1.1.178:27020", "arbiterOnly" : true } ] } > > rs.initiate(config); 初始化副本集########eeeerrrr { "ok" : 1, "operationTime" : Timestamp(1583907929, 1), "$clusterTime" : { "clusterTime" : Timestamp(1583907929, 1), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } } } ``` ### 5、查看节点状态 ``` rs02:PRIMARY> rs.status() { "set" : "rs02", "date" : ISODate("2020-03-13T07:11:09.427Z"), "myState" : 1, "term" : NumberLong(1), "syncingTo" : "", "syncSourceHost" : "", "syncSourceId" : -1, "heartbeatIntervalMillis" : NumberLong(2000), "optimes" : { "lastCommittedOpTime" : { "ts" : Timestamp(1584083465, 1), "t" : NumberLong(1) }, "readConcernMajorityOpTime" : { "ts" : Timestamp(1584083465, 1), "t" : NumberLong(1) }, "appliedOpTime" : { "ts" : Timestamp(1584083465, 1), "t" : NumberLong(1) }, "durableOpTime" : { "ts" : Timestamp(1584083465, 1), "t" : NumberLong(1) } }, "members" : [ { "_id" : 0, "name" : "10.1.1.159:27020", "health" : 1, "state" : 1, "stateStr" : "PRIMARY", #主节点 "uptime" : 185477, "optime" : { "ts" : Timestamp(1584083465, 1), "t" : NumberLong(1) }, "optimeDate" : ISODate("2020-03-13T07:11:05Z"), "syncingTo" : "", "syncSourceHost" : "", "syncSourceId" : -1, "infoMessage" : "", "electionTime" : Timestamp(1583907939, 1), "electionDate" : ISODate("2020-03-11T06:25:39Z"), "configVersion" : 1, "self" : true, "lastHeartbeatMessage" : "" }, { "_id" : 1, "name" : "10.1.1.77:27020", "health" : 1, "state" : 2, "stateStr" : "SECONDARY", #从节点 "uptime" : 175540, "optime" : { "ts" : Timestamp(1584083465, 1), "t" : NumberLong(1) }, "optimeDurable" : { "ts" : Timestamp(1584083465, 1), "t" : NumberLong(1) }, "optimeDate" : ISODate("2020-03-13T07:11:05Z"), "optimeDurableDate" : ISODate("2020-03-13T07:11:05Z"), "lastHeartbeat" : ISODate("2020-03-13T07:11:08.712Z"), "lastHeartbeatRecv" : ISODate("2020-03-13T07:11:08.711Z"), "pingMs" : NumberLong(0), "lastHeartbeatMessage" : "", "syncingTo" : "10.1.1.159:27020", "syncSourceHost" : "10.1.1.159:27020", "syncSourceId" : 0, "infoMessage" : "", "configVersion" : 1 }, { "_id" : 2, "name" : "10.1.1.178:27020", "health" : 1, "state" : 7, "stateStr" : "ARBITER", #仲裁节点 "uptime" : 175540, "lastHeartbeat" : ISODate("2020-03-13T07:11:08.712Z"), "lastHeartbeatRecv" : ISODate("2020-03-13T07:11:08.711Z"), "pingMs" : NumberLong(0), "lastHeartbeatMessage" : "", "syncingTo" : "", "syncSourceHost" : "", "syncSourceId" : -1, "infoMessage" : "", "configVersion" : 1 } ], "ok" : 1, "operationTime" : Timestamp(1584083465, 1), "$clusterTime" : { "clusterTime" : Timestamp(1584083465, 1), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } } } rs02:PRIMARY> ``` ### 7、现在副本集状态： >10.1.1.178:27020 ARBITER 仲裁节点 10.1.1.77:27020 SECONDARY 从节点 10.1.1.159:27020 PRIMARY 主节点 我们插入一些数据查，然后将主节点停掉， 仲裁节点的日志 我们可以看到，当节点10.1.1.159宕机以后，重新选举了：Member 10.1.1.77:27010 is now in state PRIMARY ``` 2020-03-18T14:34:53.636+0800 I NETWORK [conn9] end connection 10.1.1.159:49160 (1 connection now open) 2020-03-18T14:34:54.465+0800 I CONNPOOL [Replication] dropping unhealthy pooled connection to 10.1.1.159:27010 2020-03-18T14:34:54.465+0800 I CONNPOOL [Replication] after drop, pool was empty, going to spawn some connections 2020-03-18T14:34:54.465+0800 I ASIO [Replication] Connecting to 10.1.1.159:27010 ...... 2020-03-18T14:35:02.473+0800 I ASIO [Replication] Failed to connect to 10.1.1.159:27010 - HostUnreachable: Error connecting to 10.1.1.159:27010 :: caused by :: Connection refused 2020-03-18T14:35:02.473+0800 I CONNPOOL [Replication] Dropping all pooled connections to 10.1.1.159:27010 due to HostUnreachable: Error connecting to 10.1.1.159:27010 :: caused by :: Connection refused 2020-03-18T14:35:02.473+0800 I REPL_HB [replexec-8] Error in heartbeat (requestId: 662) to 10.1.1.159:27010, response status: HostUnreachable: Error connecting to 10.1.1.159:27010 :: caused by :: Connection refused 2020-03-18T14:35:04.463+0800 I REPL [replexec-5] Member 10.1.1.77:27010 is now in state PRIMARY 2020-03-18T14:35:04.473+0800 I ASIO [Replication] Connecting to 10.1.1.159:27010 2020-03-18T14:35:04.473+0800 I ASIO [Replication] Failed to connect to 10.1.1.159:27010 - HostUnreachable: Error connecting to 10.1.1.159:27010 :: caused by :: Connection refused 2020-03-18T14:35:04.473+0800 I CONNPOOL [Replication] Dropping all pooled connections to 10.1.1.159:27010 due to HostUnreachable: Error connecting to 10.1.1.159:27010 :: caused by :: Connection refused ``` 架构也就变成了下图：  目前副本集搭建完成，也测试了当一个节点出现问题以后（至少三个节点），并不会影响服务正常读写。 下一章我们开始添加用户：