MongoDB分片集群shard扩缩容

文章目录

• 一、分片shard节点缩容
• 二、分片shard节点扩容

一、分片shard节点缩容

Mongodb分片集群shard节点缩容相对是比较简单的，可以利用MongoDB自身的平衡器来将预下线中的分片中存储的数据进行转移，待预下线shard节点中无任何数据库，进行下线处理。所有的下线操作通过mongos进行管理实现。

1、查看分片集群是否开启平衡器

mongos> sh.getBalancerState()
true

2、发起删除分片节点命令，平衡器开始自动迁移数据

-- 查看当前集群状态
mongos> sh.status()
--- Sharding Status ---sharding version: {"_id" : 1,"minCompatibleVersion" : 5,"currentVersion" : 6,"clusterId" : ObjectId("6069b489d65227986c7fbe7a")}shards:{  "_id" : "shard1",  "host" : "shard1/172.16.104.12:27001,172.16.104.13:27001,172.16.104.14:27001",  "state" : 1 }{  "_id" : "shard2",  "host" : "shard2/172.16.104.12:27002,172.16.104.13:27002,172.16.104.14:27002",  "state" : 1 }{  "_id" : "shard3",  "host" : "shard3/172.16.104.12:27003,172.16.104.13:27003,172.16.104.14:27003",  "state" : 1 }             //预下线shard节点active mongoses:"4.0.22" : 3autosplit:Currently enabled: yesbalancer:Currently enabled:  yesCurrently running:  noFailed balancer rounds in last 5 attempts:  0Migration Results for the last 24 hours:682 : Successdatabases:{  "_id" : "config",  "primary" : "config",  "partitioned" : true }config.system.sessionsshard key: { "_id" : 1 }unique: falsebalancing: truechunks:shard1	342shard2	341shard3	341too many chunks to print, use verbose if you want to force print{  "_id" : "db1",  "primary" : "shard2",  "partitioned" : true,  "version" : {  "uuid" : UUID("bd30b8c8-a9f5-4bdd-917e-2734e4a64ae1"),  "lastMod" : 1 } }db1.test1shard key: { "_id" : "hashed" }unique: falsebalancing: truechunks:shard1	2shard2	2shard3	2{ "_id" : { "$minKey" : 1 } } -->> { "_id" : NumberLong("-6148914691236517204") } on : shard1 Timestamp(1, 0){ "_id" : NumberLong("-6148914691236517204") } -->> { "_id" : NumberLong("-3074457345618258602") } on : shard1 Timestamp(1, 1){ "_id" : NumberLong("-3074457345618258602") } -->> { "_id" : NumberLong(0) } on : shard2 Timestamp(1, 2){ "_id" : NumberLong(0) } -->> { "_id" : NumberLong("3074457345618258602") } on : shard2 Timestamp(1, 3){ "_id" : NumberLong("3074457345618258602") } -->> { "_id" : NumberLong("6148914691236517204") } on : shard3 Timestamp(1, 4){ "_id" : NumberLong("6148914691236517204") } -->> { "_id" : { "$maxKey" : 1 } } on : shard3 Timestamp(1, 5)-- 发起分片节点删除，平衡器开始自动将数据进行迁移
mongos> use admin                                           # 必须进入admin库下
switched to db admin
mongos> db.runCommand({removeShard:"shard3"})               # 发起删除shard命令
{"msg" : "draining started successfully","state" : "started","shard" : "shard3","note" : "you need to drop or movePrimary these databases","dbsToMove" : [ ],"ok" : 1,"operationTime" : Timestamp(1617550950, 2),"$clusterTime" : {"clusterTime" : Timestamp(1617550950, 2),"signature" : {"hash" : BinData(0,"Kb0MDb4APzAlY6/leqWrfUw6KsA="),"keyId" : NumberLong("6947282400699219974")}}
}

3、等待平衡器将需要删除的分片节点中数据全部迁移完毕

mongos> sh.status()
--- Sharding Status ---sharding version: {"_id" : 1,"minCompatibleVersion" : 5,"currentVersion" : 6,"clusterId" : ObjectId("6069b489d65227986c7fbe7a")}shards:{  "_id" : "shard1",  "host" : "shard1/172.16.104.12:27001,172.16.104.13:27001,172.16.104.14:27001",  "state" : 1 }{  "_id" : "shard2",  "host" : "shard2/172.16.104.12:27002,172.16.104.13:27002,172.16.104.14:27002",  "state" : 1 }{  "_id" : "shard3",  "host" : "shard3/172.16.104.12:27003,172.16.104.13:27003,172.16.104.14:27003",  "state" : 1,  "draining" : true }     //预下线shard节点数据迁移完毕，处于一个可直接下线状态active mongoses:"4.0.22" : 3autosplit:Currently enabled: yesbalancer:Currently enabled:  yesCurrently running:  noFailed balancer rounds in last 5 attempts:  0Migration Results for the last 24 hours:1025 : Successdatabases:{  "_id" : "config",  "primary" : "config",  "partitioned" : true }config.system.sessionsshard key: { "_id" : 1 }unique: falsebalancing: truechunks:shard1	512shard2	512too many chunks to print, use verbose if you want to force print{  "_id" : "db1",  "primary" : "shard2",  "partitioned" : true,  "version" : {  "uuid" : UUID("bd30b8c8-a9f5-4bdd-917e-2734e4a64ae1"),  "lastMod" : 1 } }db1.test1shard key: { "_id" : "hashed" }unique: falsebalancing: truechunks:shard1	3shard2	3{ "_id" : { "$minKey" : 1 } } -->> { "_id" : NumberLong("-6148914691236517204") } on : shard1 Timestamp(1, 0){ "_id" : NumberLong("-6148914691236517204") } -->> { "_id" : NumberLong("-3074457345618258602") } on : shard1 Timestamp(1, 1){ "_id" : NumberLong("-3074457345618258602") } -->> { "_id" : NumberLong(0) } on : shard2 Timestamp(1, 2){ "_id" : NumberLong(0) } -->> { "_id" : NumberLong("3074457345618258602") } on : shard2 Timestamp(1, 3){ "_id" : NumberLong("3074457345618258602") } -->> { "_id" : NumberLong("6148914691236517204") } on : shard2 Timestamp(2, 0){ "_id" : NumberLong("6148914691236517204") } -->> { "_id" : { "$maxKey" : 1 } } on : shard1 Timestamp(3, 0)mongos>

4、真正从分片集群中删除shard副本集信息

mongos> use admin
switched to db admin
mongos> db.runCommand({removeShard:"shard3"})                                       # 下线shard节点
{"msg" : "removeshard completed successfully","state" : "completed","shard" : "shard3","ok" : 1,"operationTime" : Timestamp(1617551668, 3),"$clusterTime" : {"clusterTime" : Timestamp(1617551668, 3),"signature" : {"hash" : BinData(0,"zVvEDlDNJajf386J/wat3ePCwYs="),"keyId" : NumberLong("6947282400699219974")}}
}

5、检查分片缩容后的分片集群状态

mongos> sh.status()
--- Sharding Status ---sharding version: {"_id" : 1,"minCompatibleVersion" : 5,"currentVersion" : 6,"clusterId" : ObjectId("6069b489d65227986c7fbe7a")}shards:{  "_id" : "shard1",  "host" : "shard1/172.16.104.12:27001,172.16.104.13:27001,172.16.104.14:27001",  "state" : 1 }{  "_id" : "shard2",  "host" : "shard2/172.16.104.12:27002,172.16.104.13:27002,172.16.104.14:27002",  "state" : 1 }active mongoses:"4.0.22" : 3autosplit:Currently enabled: yesbalancer:Currently enabled:  yesCurrently running:  noFailed balancer rounds in last 5 attempts:  0Migration Results for the last 24 hours:1025 : Successdatabases:{  "_id" : "config",  "primary" : "config",  "partitioned" : true }config.system.sessionsshard key: { "_id" : 1 }unique: falsebalancing: truechunks:shard1	512shard2	512too many chunks to print, use verbose if you want to force print{  "_id" : "db1",  "primary" : "shard2",  "partitioned" : true,  "version" : {  "uuid" : UUID("bd30b8c8-a9f5-4bdd-917e-2734e4a64ae1"),  "lastMod" : 1 } }db1.test1shard key: { "_id" : "hashed" }unique: falsebalancing: truechunks:shard1	3shard2	3{ "_id" : { "$minKey" : 1 } } -->> { "_id" : NumberLong("-6148914691236517204") } on : shard1 Timestamp(1, 0){ "_id" : NumberLong("-6148914691236517204") } -->> { "_id" : NumberLong("-3074457345618258602") } on : shard1 Timestamp(1, 1){ "_id" : NumberLong("-3074457345618258602") } -->> { "_id" : NumberLong(0) } on : shard2 Timestamp(1, 2){ "_id" : NumberLong(0) } -->> { "_id" : NumberLong("3074457345618258602") } on : shard2 Timestamp(1, 3){ "_id" : NumberLong("3074457345618258602") } -->> { "_id" : NumberLong("6148914691236517204") } on : shard2 Timestamp(2, 0){ "_id" : NumberLong("6148914691236517204") } -->> { "_id" : { "$maxKey" : 1 } } on : shard1 Timestamp(3, 0)mongos>

二、分片shard节点扩容

MongoDB分片集群shard节点的扩容也相对比较简单。首先我们需要将需要扩容的shard副本集提前部署好，然后通过mongos将预上线shard节点添加至分片集群，MongoDB的平衡器自动将数据迁移至新增shard节点进行数据平衡。

1、搭建部署需要扩容的分片集群

1）初始化相关目录

# /data/mongodb40/shard3/{data,logs,conf}

2）拷贝相关的keyfile文件

# cp -r /data/mongodb40/shard2/conf/KeyFile.file  /data/mongodb40/shard3/conf

3）修改配置

-- 配置文件[root@sdw3 ~]# cat /data/mongodb40/shard3/conf/config.conf
systemLog:verbosity: 0quiet: falsetraceAllExceptions: falsepath: "/data/mongodb40/shard3/logs/config.log"logAppend: truelogRotate: reopendestination: file
processManagement:fork: truepidFilePath: "/data/mongodb40/shard3/conf/config.pid"
net:port: 27003                                                          # 端口bindIp: 0.0.0.0maxIncomingConnections: 2000wireObjectCheck: true
security:keyFile: "/data/mongodb40/shard3/conf/KeyFile.file"clusterAuthMode: keyFileauthorization: enabled#authorization: disabled
storage:dbPath: /data/mongodb40/shard3/data#indexBuildRetry: truejournal:enabled: truecommitIntervalMs: 100directoryPerDB: truesyncPeriodSecs: 60engine: wiredTigerwiredTiger:engineConfig:cacheSizeGB: 256#journalCompressor: snappydirectoryForIndexes: falsecollectionConfig:blockCompressor: snappyindexConfig:prefixCompression: falseoperationProfiling:slowOpThresholdMs: 100mode: slowOp
replication:#oplogSizeMB: 1024replSetName: shard3secondaryIndexPrefetch: allenableMajorityReadConcern: false
sharding:clusterRole: shardsvr                                                # 标识为shard角色

3）启动shard3副本集中各个节点并进行副本集初始化

> cnf = {"_id":"shard3","members":[{"_id":1,"host":"172.16.104.12:27003","priority":1},{"_id":2, "host":"172.16.104.13:27003","priority":1},{"_id":3, "host":"172.16.104.14:27003","priority":10}]}
> rs.initiate(cnf)

4）创建超级用户信息

shard3:PRIMARY> use admin
shard3:PRIMARY> db.createUser({"user":"root","pwd":"123","roles":[{role:"root",db:"admin"}]})

2、查看当前分片集群信息

mongos> sh.status()
--- Sharding Status ---sharding version: {"_id" : 1,"minCompatibleVersion" : 5,"currentVersion" : 6,"clusterId" : ObjectId("6069b489d65227986c7fbe7a")}shards:{  "_id" : "shard1",  "host" : "shard1/172.16.104.12:27001,172.16.104.13:27001,172.16.104.14:27001",  "state" : 1 }{  "_id" : "shard2",  "host" : "shard2/172.16.104.12:27002,172.16.104.13:27002,172.16.104.14:27002",  "state" : 1 }active mongoses:"4.0.22" : 3autosplit:Currently enabled: yesbalancer:Currently enabled:  yesCurrently running:  noFailed balancer rounds in last 5 attempts:  0Migration Results for the last 24 hours:1025 : Successdatabases:{  "_id" : "config",  "primary" : "config",  "partitioned" : true }config.system.sessionsshard key: { "_id" : 1 }unique: falsebalancing: truechunks:shard1	512shard2	512too many chunks to print, use verbose if you want to force print{  "_id" : "db1",  "primary" : "shard2",  "partitioned" : true,  "version" : {  "uuid" : UUID("bd30b8c8-a9f5-4bdd-917e-2734e4a64ae1"),  "lastMod" : 1 } }db1.test1shard key: { "_id" : "hashed" }unique: falsebalancing: truechunks:shard1	3shard2	3{ "_id" : { "$minKey" : 1 } } -->> { "_id" : NumberLong("-6148914691236517204") } on : shard1 Timestamp(1, 0){ "_id" : NumberLong("-6148914691236517204") } -->> { "_id" : NumberLong("-3074457345618258602") } on : shard1 Timestamp(1, 1){ "_id" : NumberLong("-3074457345618258602") } -->> { "_id" : NumberLong(0) } on : shard2 Timestamp(1, 2){ "_id" : NumberLong(0) } -->> { "_id" : NumberLong("3074457345618258602") } on : shard2 Timestamp(1, 3){ "_id" : NumberLong("3074457345618258602") } -->> { "_id" : NumberLong("6148914691236517204") } on : shard2 Timestamp(2, 0){ "_id" : NumberLong("6148914691236517204") } -->> { "_id" : { "$maxKey" : 1 } } on : shard1 Timestamp(3, 0)mongos>

3、通过mongos添加新增分片副本集信息

mongos> use admin
switched to db admin
mongos> sh.addShard("shard3/172.16.104.12:27003,172.16.104.13:27003,172.16.104.14:27003")
{"shardAdded" : "shard3","ok" : 1,"operationTime" : Timestamp(1617552097, 2),"$clusterTime" : {"clusterTime" : Timestamp(1617552097, 2),"signature" : {"hash" : BinData(0,"wVW+P1UwUk4ZW3Cti2bcIGO3djc="),"keyId" : NumberLong("6947282400699219974")}}
}

4、此时mongos平衡器开始讲之前一存在的分片中数据向新增节点中进行迁移，等待一段时间后可在通过sh.status()查看是否迁移完毕

mongos> sh.status()
--- Sharding Status ---sharding version: {"_id" : 1,"minCompatibleVersion" : 5,"currentVersion" : 6,"clusterId" : ObjectId("6069b489d65227986c7fbe7a")}shards:{  "_id" : "shard1",  "host" : "shard1/172.16.104.12:27001,172.16.104.13:27001,172.16.104.14:27001",  "state" : 1 }{  "_id" : "shard2",  "host" : "shard2/172.16.104.12:27002,172.16.104.13:27002,172.16.104.14:27002",  "state" : 1 }{  "_id" : "shard3",  "host" : "shard3/172.16.104.12:27003,172.16.104.13:27003,172.16.104.14:27003",  "state" : 1 }active mongoses:"4.0.22" : 3autosplit:Currently enabled: yesbalancer:Currently enabled:  yesCurrently running:  noFailed balancer rounds in last 5 attempts:  0Migration Results for the last 24 hours:1367 : Successdatabases:{  "_id" : "config",  "primary" : "config",  "partitioned" : true }config.system.sessionsshard key: { "_id" : 1 }unique: falsebalancing: truechunks:shard1	342shard2	342shard3	340too many chunks to print, use verbose if you want to force print{  "_id" : "db1",  "primary" : "shard2",  "partitioned" : true,  "version" : {  "uuid" : UUID("bd30b8c8-a9f5-4bdd-917e-2734e4a64ae1"),  "lastMod" : 1 } }db1.test1shard key: { "_id" : "hashed" }unique: falsebalancing: truechunks:shard1	2shard2	2shard3	2{ "_id" : { "$minKey" : 1 } } -->> { "_id" : NumberLong("-6148914691236517204") } on : shard3 Timestamp(4, 0){ "_id" : NumberLong("-6148914691236517204") } -->> { "_id" : NumberLong("-3074457345618258602") } on : shard1 Timestamp(4, 1){ "_id" : NumberLong("-3074457345618258602") } -->> { "_id" : NumberLong(0) } on : shard3 Timestamp(5, 0){ "_id" : NumberLong(0) } -->> { "_id" : NumberLong("3074457345618258602") } on : shard2 Timestamp(5, 1){ "_id" : NumberLong("3074457345618258602") } -->> { "_id" : NumberLong("6148914691236517204") } on : shard2 Timestamp(2, 0){ "_id" : NumberLong("6148914691236517204") } -->> { "_id" : { "$maxKey" : 1 } } on : shard1 Timestamp(3, 0)mongos>

本文来自互联网用户投稿，文章观点仅代表作者本人，不代表本站立场，不承担相关法律责任。如若转载，请注明出处。 如若内容造成侵权/违法违规/事实不符，请点击【内容举报】进行投诉反馈！