docker-compose 部署MongoDB4.0 部署replica set(副本集)集群多服务器

准备三台服务器 192.168.0.11 192.168.0.12 192.168.0.13

生成keyFile

MongoDB使用keyfile认证，副本集中的每个mongod实例使用keyfile内容作为认证其他成员的共享密码。mongod实例只有拥有正确的keyfile才可以加入副本集。
keyFile的内容必须是6到1024个字符的长度，且副本集所有成员的keyFile内容必须相同。
有一点要注意是的：在UNIX系统中，keyFile必须没有组权限或完全权限（也就是权限要设置成X00的形式）。Windows系统中，keyFile权限没有被检查。
可以使用任意方法生成keyFile。例如，如下操作使用openssl生成复杂的随机的1024个字符串。然后使用chmod修改文件权限，只给文件拥有者提供读权限。
这是MongoDB官方推荐keyFile的生成方式：

# 400权限是要保证安全性，否则mongod启动会报错 openssl rand -base64 756 > mongodb.key chmod 400 mongodb.key

生成完之后需要在三台机器上面配置keyFile文件副本集全靠这个来实现

在三台服务器都复制一份mongodb.key ，创建docker-compose.yml

主192.168.0.11 docker-compose.yml

version: '3.1' services: mongodb1: image: mongo restart: always container_name: mongo1 volumes: - ./data/db/mongo1:/data/db - ./mongodb.key:/data/mongodb.key ports: - 27017:27017 environment: MONGO_INITDB_ROOT_USERNAME: root MONGO_INITDB_ROOT_PASSWORD: zeqingev command: mongod --replSet mongos --keyFile /data/mongodb.key entrypoint: - bash - -c - | chmod 400 /data/mongodb.key chown 999:999 /data/mongodb.key exec docker-entrypoint.sh $$@

从192.168.0.12 docker-compose.yml

version: '3.1' services: mongodb2: image: mongo restart: always container_name: mongo2 volumes: - ./data/db/mongo2:/data/db - ./mongodb.key:/data/mongodb.key ports: - 27017:27017 environment: MONGO_INITDB_ROOT_USERNAME: root MONGO_INITDB_ROOT_PASSWORD: zeqingev command: mongod --replSet mongos --keyFile /data/mongodb.key entrypoint: - bash - -c - | chmod 400 /data/mongodb.key chown 999:999 /data/mongodb.key exec docker-entrypoint.sh $$@

从192.168.0.13 docker-compose.yml

version: '3.1' services: mongodb13: image: mongo restart: always container_name: mongo3 volumes: - ./data/db/mongo3:/data/db - ./mongodb.key:/data/mongodb.key ports: - 27017:27017 environment: MONGO_INITDB_ROOT_USERNAME: root MONGO_INITDB_ROOT_PASSWORD: zeqingev command: mongod --replSet mongos --keyFile /data/mongodb.key entrypoint: - bash - -c - | chmod 400 /data/mongodb.key chown 999:999 /data/mongodb.key exec docker-entrypoint.sh $$@

文件详解
chown 999:999 /data/mongodb.key 999用户是容器中的mongod用户，通过chown修改文件用户权限
mongod –replSet mongos –keyFile /data/mongodb.key 启动命令，–replSet mongos 以副本集形式启动并将副本集名字命名为 mongos ，–keyFile /data/mongodb.key 设置keyFile，用于副本集通信，文件通过 volumes 映射到容器内
networks 创建容器在同一局域网下，容器之间通信

配置副本集
切换到docker-compose.yml所在目录，执行命令docker-compose up -d启动数据库，-d 表示后台启动并运行所有的容器。
通过命令 docker exec -it mongo1 /bin/bash 进入容器进行配置

进入容器之后，通过mongo命令行进入数据库，因为在docker-compose 配置文件中设置了数据库账密，不输入账密会无法进行设置，查看副本集配置时会提示无权限。

此时输入 rs.status() 会提示没有配置副本集
```
> rs.status() { "ok" : 0, "errmsg" : "no replset config has been received", "code" : 94, "codeName" : "NotYetInitialized" } > 
```
复制以下内容初始化副本集配置，其中ip是服务器的公网IP，如果设置了容器IP，数据库之间能进行通信，但是通过连接无法正确连接副本集，_id 的值是 docker-compose 配置文件启动命令设置的 –replSet mongos 副本集名称，这是最基础的配置， rs.initiate() 触发选举，并选举出一个成员作为primary。
```
rs.initiate({ _id: "mongos", members: [ { _id : 0, host : "192.168.0.11:27017" }, { _id : 1, host : "192.168.0.12:27017" }, { _id : 2, host : "192.168.0.13:27017" } ] }); 
```
执行初始化配置命令，显示{ "ok" : 1 }就代表已经成功了，等待一会儿就会选举出PRIMARY节点，可以用rs.status()查看当前副本集状态。

> rs.initiate({ ... _id: "mongos", ... members: [ ... { _id : 0, host : "192.168.0.11:27017" }, ... { _id : 1, host : "192.168.0.12:27017" }, ... { _id : 2, host : "192.168.0.13:27017" } ... ] ... }); { "ok" : 1 } mongos:SECONDARY> mongos:PRIMARY> mongos:PRIMARY> rs.status() { "set" : "mongos", "date" : ISODate("2019-07-14T06:01:48.574Z"), "myState" : 1, "term" : NumberLong(1), "syncingTo" : "", "syncSourceHost" : "", "syncSourceId" : -1, "heartbeatIntervalMillis" : NumberLong(2000), "optimes" : { "lastCommittedOpTime" : { "ts" : Timestamp(1563084092, 1), "t" : NumberLong(1) }, "readConcernMajorityOpTime" : { "ts" : Timestamp(1563084092, 1), "t" : NumberLong(1) }, "appliedOpTime" : { "ts" : Timestamp(1563084092, 1), "t" : NumberLong(1) }, "durableOpTime" : { "ts" : Timestamp(1563084092, 1), "t" : NumberLong(1) } }, "lastStableCheckpointTimestamp" : Timestamp(1563084091, 1), "members" : [ { "_id" : 0, "name" : "192.168.0.11:27017", "health" : 1, "state" : 1, "stateStr" : "PRIMARY", "uptime" : 185, "optime" : { "ts" : Timestamp(1563084092, 1), "t" : NumberLong(1) }, "optimeDate" : ISODate("2019-07-14T06:01:32Z"), "syncingTo" : "", "syncSourceHost" : "", "syncSourceId" : -1, "infoMessage" : "could not find member to sync from", "electionTime" : Timestamp(1563084090, 1), "electionDate" : ISODate("2019-07-14T06:01:30Z"), "configVersion" : 1, "self" : true, "lastHeartbeatMessage" : "" }, { "_id" : 1, "name" : "192.168.0.12:27017", "health" : 1, "state" : 2, "stateStr" : "SECONDARY", "uptime" : 28, "optime" : { "ts" : Timestamp(1563084092, 1), "t" : NumberLong(1) }, "optimeDurable" : { "ts" : Timestamp(1563084092, 1), "t" : NumberLong(1) }, "optimeDate" : ISODate("2019-07-14T06:01:32Z"), "optimeDurableDate" : ISODate("2019-07-14T06:01:32Z"), "lastHeartbeat" : ISODate("2019-07-14T06:01:48.252Z"), "lastHeartbeatRecv" : ISODate("2019-07-14T06:01:48.519Z"), "pingMs" : NumberLong(0), "lastHeartbeatMessage" : "", "syncingTo" : "192.168.0.11:27017", "syncSourceHost" : "192.168.0.11:27017", "syncSourceId" : 0, "infoMessage" : "", "configVersion" : 1 }, { "_id" : 2, "name" : "192.168.0.13:27017", "health" : 1, "state" : 2, "stateStr" : "SECONDARY", "uptime" : 28, "optime" : { "ts" : Timestamp(1563084092, 1), "t" : NumberLong(1) }, "optimeDurable" : { "ts" : Timestamp(1563084092, 1), "t" : NumberLong(1) }, "optimeDate" : ISODate("2019-07-14T06:01:32Z"), "optimeDurableDate" : ISODate("2019-07-14T06:01:32Z"), "lastHeartbeat" : ISODate("2019-07-14T06:01:48.252Z"), "lastHeartbeatRecv" : ISODate("2019-07-14T06:01:48.512Z"), "pingMs" : NumberLong(0), "lastHeartbeatMessage" : "", "syncingTo" : "192.168.0.11:27017", "syncSourceHost" : "192.168.0.11:27017", "syncSourceId" : 0, "infoMessage" : "", "configVersion" : 1 } ], "ok" : 1, "operationTime" : Timestamp(1563084092, 1), "$clusterTime" : { "clusterTime" : Timestamp(1563084092, 1), "signature" : { "hash" : BinData(0,"5XoSC0ilUaKemlTAx+Cx/xkoKc8="), "keyId" : NumberLong("6713395051742887937") } } } mongos:PRIMARY>

故障转移

在副本集模式下，如果Primary节点宕机不可用，集群会选举出新的Primary节点所以手动停止主节点的mongo1 等待30s 再重新启动主mongo1 再去查看当前的节点状态 rs.status()

{ "set" : "mongos", "date" : ISODate("2021-04-08T04:15:24.485Z"), "myState" : 2, "term" : NumberLong(6), "syncSourceHost" : "192.168.0.12:27017", "syncSourceId" : 2, "heartbeatIntervalMillis" : NumberLong(2000), "majorityVoteCount" : 2, "writeMajorityCount" : 2, "votingMembersCount" : 3, "writableVotingMembersCount" : 3, "optimes" : { "lastCommittedOpTime" : { "ts" : Timestamp(1617855317, 1), "t" : NumberLong(6) }, "lastCommittedWallTime" : ISODate("2021-04-08T04:15:17.584Z"), "readConcernMajorityOpTime" : { "ts" : Timestamp(1617855317, 1), "t" : NumberLong(6) }, "readConcernMajorityWallTime" : ISODate("2021-04-08T04:15:17.584Z"), "appliedOpTime" : { "ts" : Timestamp(1617855317, 1), "t" : NumberLong(6) }, "durableOpTime" : { "ts" : Timestamp(1617855317, 1), "t" : NumberLong(6) }, "lastAppliedWallTime" : ISODate("2021-04-08T04:15:17.584Z"), "lastDurableWallTime" : ISODate("2021-04-08T04:15:17.584Z") }, "lastStableRecoveryTimestamp" : Timestamp(1617855317, 1), "electionParticipantMetrics" : { "votedForCandidate" : true, "electionTerm" : NumberLong(6), "lastVoteDate" : ISODate("2021-04-08T03:58:37.425Z"), "electionCandidateMemberId" : 1, "voteReason" : "", "lastAppliedOpTimeAtElection" : { "ts" : Timestamp(1617854283, 1), "t" : NumberLong(4) }, "maxAppliedOpTimeInSet" : { "ts" : Timestamp(1617854283, 1), "t" : NumberLong(4) }, "priorityAtElection" : 1, "newTermStartDate" : ISODate("2021-04-08T03:58:37.562Z"), "newTermAppliedDate" : ISODate("2021-04-08T03:58:38.553Z") }, "members" : [ { "_id" : 0, "name" : "192.168.0.11:27017", "health" : 1, "state" : 2, "stateStr" : "SECONDARY", "uptime" : 1026, "optime" : { "ts" : Timestamp(1617855317, 1), "t" : NumberLong(6) }, "optimeDate" : ISODate("2021-04-08T04:15:17Z"), "syncSourceHost" : "192.168.0.12:27017", "syncSourceId" : 2, "infoMessage" : "", "configVersion" : 1, "configTerm" : 6, "self" : true, "lastHeartbeatMessage" : "" }, { "_id" : 1, "name" : "192.168.0.13:27017", "health" : 1, "state" : 1, "stateStr" : "PRIMARY", "uptime" : 1021, "optime" : { "ts" : Timestamp(1617855317, 1), "t" : NumberLong(6) }, "optimeDurable" : { "ts" : Timestamp(1617855317, 1), "t" : NumberLong(6) }, "optimeDate" : ISODate("2021-04-08T04:15:17Z"), "optimeDurableDate" : ISODate("2021-04-08T04:15:17Z"), "lastHeartbeat" : ISODate("2021-04-08T04:15:24.337Z"), "lastHeartbeatRecv" : ISODate("2021-04-08T04:15:22.572Z"), "pingMs" : NumberLong(2), "lastHeartbeatMessage" : "", "syncSourceHost" : "", "syncSourceId" : -1, "infoMessage" : "", "electionTime" : Timestamp(1617854317, 1), "electionDate" : ISODate("2021-04-08T03:58:37Z"), "configVersion" : 1, "configTerm" : 6 }, { "_id" : 2, "name" : "192.168.0.12:27017", "health" : 1, "state" : 2, "stateStr" : "SECONDARY", "uptime" : 1016, "optime" : { "ts" : Timestamp(1617855317, 1), "t" : NumberLong(6) }, "optimeDurable" : { "ts" : Timestamp(1617855317, 1), "t" : NumberLong(6) }, "optimeDate" : ISODate("2021-04-08T04:15:17Z"), "optimeDurableDate" : ISODate("2021-04-08T04:15:17Z"), "lastHeartbeat" : ISODate("2021-04-08T04:15:23.991Z"), "lastHeartbeatRecv" : ISODate("2021-04-08T04:15:23.799Z"), "pingMs" : NumberLong(2), "lastHeartbeatMessage" : "", "syncSourceHost" : "192.168.0.13:27017", "syncSourceId" : 1, "infoMessage" : "", "configVersion" : 1, "configTerm" : 6 } ], "ok" : 1, "$clusterTime" : { "clusterTime" : Timestamp(1617855317, 1), "signature" : { "hash" : BinData(0,"8fZvmnfsJBWwRNvcKCNCK3zjvAw="), "keyId" : NumberLong("6948597425195974659") } }, "operationTime" : Timestamp(1617855317, 1) }