目录
-
-
- 1.1 MongoDB选举的原理
-
-
- 2.创建路由、配置、分片等的相关目录与文件
- 3. 配置服务器部署mongodb
- 6. 将分片配置为复制集
- 10. 启用数据库分片并进行测试
- 11. 副本节点是否已同步数据
简介
1. 副本集
开启复制集后,主节点会在 local 库下生成一个集合叫 oplog.rs,这是一个有限集合,也就是大小是固定的。其中记录的是整个mongod实例一段时间内数据库的所有变更(插入/更新/删除)操作,当空间用完时新记录自动覆盖最老的记录
MongoDB复制集(副本集):由一组实列(进程)组成;包含一个Primary节点和多个Secondary节点,用户的所有写操作写入Primary ,Secondary通过oplog来同步primary的数据;可以通过心跳检测机制,一旦primary出现故障,则就会通过仲裁节点从secondary选取一个新的主节点
Primary:主节点,由选择产生,负责客户端的写操作,产生oplog日志文件
Secondary:从节点;负责客户端的读操作;
Arbiter:仲裁节点;只参与选举的投票;不会成为Primary和secondary,任意节点宕机,复制集将不能提供服务了(无法选出Primary),这时可以给复制集添加一个Arbiter节点,即使有节点宕机,仍能选出Primary**
1.1 MongoDB选举的原理
MongoDB的节点分为三种类型,分别为标准节点(host)、被动节点(passive)和仲裁节点(arbiter)
只有标准节点才有可能被选举为活跃节点(主节点),拥有选举权。被动节点有完整副本,不可能成为活跃节点,具有选举权。仲裁节点不复制数据,不可能成为活跃节点,只有选举权。说白了就是只有标准节点才有可能被选举为主节点,即使在一个复制集中说有的标准节点都宕机,被动节点和仲裁节点也不会成为主节点
标准节点与被动节点的区别:priority值高者是标准节点,低者则为被动节点
选举规则是票数高的获胜,priority是优先权0 1000的值,相当于额外增加0 1000的票数。选举结果:票数高者获胜;若票数相同,数据新者获胜。
1.2 复制过程
-
客户端的数据进来;
-
数据操作写入到日志缓冲;
-
数据写入到数据缓冲;
-
把日志缓冲中的操作日志放到OPLOG中来;
-
返回操作结果到客户端(异步);
-
后台线程进行OPLOG复制到从节点,这个频率是非常高的,比日志刷盘频率还要高,从节点会一直监听主节点,OPLOG一有变化就会进行复制操作;
-
后台线程进行日志缓冲中的数据刷盘,非常频繁(默认100)毫秒,也可自行设置(30-60);
后台线程进行数据缓冲中的数据刷盘,默认是60秒;
2. 分片技术
复制集主要用来实现自动故障转移从而达到高可用的目的,然而,随着业务规模的增长和时间的推移,业务数据量会越来越大,当前业务数据可能只有几百GB不到,一台DB服务器足以搞定所有的工作,而一旦业务数据量扩充大几个TB几百个TB时,就会产生一台服务器无法存储的情况,此时,需要将数据按照一定的规则分配到不同的服务器进行存储、查询等,即为分片集群。分片集群要做到的事情就是数据分布式存储
存储方式:数据集被拆分成数据块(chunk),每个数据块包含多个doc,数据块分布式存储在分片集群中。
2.1 角色
Config server:MongoDB负责追踪数据块在shard上的分布信息,每个分片存储哪些数据块,叫做分片的元数据,保存在config server上的数据库 config中,一般使用3台config
server,所有config server中的config数据库必须完全相同(建议将config server部署在不同的服务器,以保证稳定性);
Shard server:将数据进行分片,拆分成数据块(chunk),每个trunk块的大小默认为64M,数据块真正存放的单位;
Mongos server:数据库集群请求的入口,所有的请求都通过mongos进行协调,查看分片的元数据,查找chunk存放位置,mongos自己就是一个请求分发中心,在生产环境通常有多mongos作为请求的入口,防止其中一个挂掉所有的mongodb请求都没有办法操作。
总结:应用请求mongos来操作mongodb的增删改查,配置服务器存储数据库元信息,并且和mongos做同步,数据最终存入在shard(分片)上,为了防止数据丢失,同步在副本集中存储了一份,仲裁节点在数据存储到分片的时候决定存储到哪个节点。
2.2 分片的片键
概述:片键是文档的一个属性字段或是一个复合索引字段,一旦建立后则不可改变,片键是拆分数据的关键的依据,如若在数据极为庞大的场景下,片键决定了数据在分片的过程中数据的存储位置,直接会影响集群的性能;
注:创建片键时,需要有一个支撑片键运行的索引;
2.3 片键分类
1.递增片键:使用时间戳,日期,自增的主键,ObjectId,_id等,此类片键的写入操作集中在一个分片服务器上,写入不具有分散性,这会导致单台服务器压力较大,但分割比较容易,这台服务器可能会成为性能瓶颈;
2.哈希片键:也称之为散列索引,使用一个哈希索引字段作为片键,优点是使数据在各节点分布比较均匀,数据写入可随机分发到每个分片服务器上,把写入的压力分散到了各个服务器上。但是读也是随机的,可能会命中更多的分片,但是缺点是无法实现范围区分;
3.组合片键: 数据库中没有比较合适的键值供片键选择,或者是打算使用的片键基数太小(即变化少如星期只有7天可变化),可以选另一个字段使用组合片键,甚至可以添加冗余字段来组合;
4.标签片键:数据存储在指定的分片服务器上,可以为分片添加tag标签,然后指定相应的tag,比如让10. . . (T)出现在shard0000上,11. . . (Q)出现在shard0001或shard0002上,就可以使用tag让均衡器指定分发;
环境介绍
分布式mongodb集群副本集+分片
CentOS Linux release 7.9.2009
Mongodb:4.0.21
IP | 路由服务端口 | 配置服务端口 | 分片1端口 | 分片2端口 | 分片3端 |
---|---|---|---|---|---|
172.16.245.102 | 27017 | 27018 | 27001 | 27002 | 27003 |
172.16.245.103 | 27017 | 27018 | 27001 | 27002 | 27003 |
172.16.245.104 | 27017 | 27018 | 27001 | 27002 | 27003 |
1.获取软件包
wget https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-4.0.21.tgz
2.创建路由、配置、分片等的相关目录与文件
三台服务器相同操作
mkdir -p /data/mongodb/conf mkdir -p /data/mongodb/data/config mkdir -p /data/mongodb/data/shard1 mkdir -p /data/mongodb/data/shard2 mkdir -p /data/mongodb/data/shard3 mkdir -p /data/mongodb/log/config.log mkdir -p /data/mongodb/log/mongos.log mkdir -p /data/mongodb/log/shard1.log mkdir -p /data/mongodb/log/shard2.log mkdir -p /data/mongodb/log/shard3.log touch /data/mongodb/log/config.log/config.log touch /data/mongodb/log/mongos.log/mongos.log touch /data/mongodb/log/shard1.log/shard1.log touch /data/mongodb/log/shard2.log/shard2.log touch /data/mongodb/log/shard3.log/shard3.log
3. 配置服务器部署mongodb
3台服务器执行相同操作
[root@node5 conf]# vim /data/mongodb/conf/config.conf [root@node5 conf]# cat /data/mongodb/conf/config.conf dbpath=/data/mongodb/data/config logpath=/data/mongodb/log/config.log/config.log port=27018 #端口号 logappend=true fork=true maxConns=5000 replSet=configs #副本集名称 configsvr=true bind_ip=0.0.0.0
4. 配置复本集
分别启动三台服务器的配置服务
[root@node5 conf]# /data/mongodb/bin/mongod -f /data/mongodb/conf/config.conf
连接mongo,只需在任意一台机器执行即可
[root@node5 conf]# /data/mongodb/bin/mongo --host 172.16.245.102 --port 27018
进入数据库以后切换数据库
use admin
初始化副本集
rs.initiate({_id:"configs",members:[{_id:0,host:"172.16.245.102:27018"},{_id:1,host:"172.16.245.103:27018"}, {_id:2,host:"172.16.245.104:27018"}]})
其中_id:”configs”的configs是上面config.conf配置文件里的复制集名称,把三台服务器的(指定相应的IP)配置服务组成复制集
查看状态
configs:PRIMARY> rs.status() { "set" : "configs", #副本集名称 "date" : ISODate("2020-12-22T06:39:04.184Z"), "myState" : 1, "term" : NumberLong(1), "syncingTo" : "", "syncSourceHost" : "", "syncSourceId" : -1, "configsvr" : true, "heartbeatIntervalMillis" : NumberLong(2000), "optimes" : { "lastCommittedOpTime" : { "ts" : Timestamp(1608619142, 1), "t" : NumberLong(1) }, "readConcernMajorityOpTime" : { "ts" : Timestamp(1608619142, 1), "t" : NumberLong(1) }, "appliedOpTime" : { "ts" : Timestamp(1608619142, 1), "t" : NumberLong(1) }, "durableOpTime" : { "ts" : Timestamp(1608619142, 1), "t" : NumberLong(1) } }, "lastStableCheckpointTimestamp" : Timestamp(1608619122, 1), "electionCandidateMetrics" : { "lastElectionReason" : "electionTimeout", "lastElectionDate" : ISODate("2020-12-22T05:31:42.975Z"), "electionTerm" : NumberLong(1), "lastCommittedOpTimeAtElection" : { "ts" : Timestamp(0, 0), "t" : NumberLong(-1) }, "lastSeenOpTimeAtElection" : { "ts" : Timestamp(1608615092, 1), "t" : NumberLong(-1) }, "numVotesNeeded" : 2, "priorityAtElection" : 1, "electionTimeoutMillis" : NumberLong(10000), "numCatchUpOps" : NumberLong(0), "newTermStartDate" : ISODate("2020-12-22T05:31:42.986Z"), "wMajorityWriteAvailabilityDate" : ISODate("2020-12-22T05:31:44.134Z") }, "members" : [ { "_id" : 0, "name" : "172.16.245.102:27018", #副本1 "health" : 1, "state" : 1, "stateStr" : "PRIMARY", "uptime" : 4383, "optime" : { "ts" : Timestamp(1608619142, 1), "t" : NumberLong(1) }, "optimeDate" : ISODate("2020-12-22T06:39:02Z"), "syncingTo" : "", "syncSourceHost" : "", "syncSourceId" : -1, "infoMessage" : "", "electionTime" : Timestamp(1608615102, 1), "electionDate" : ISODate("2020-12-22T05:31:42Z"), "configVersion" : 1, "self" : true, "lastHeartbeatMessage" : "" }, { "_id" : 1, "name" : "172.16.245.103:27018", #副本2 "health" : 1, "state" : 2, "stateStr" : "SECONDARY", "uptime" : 4052, "optime" : { "ts" : Timestamp(1608619142, 1), "t" : NumberLong(1) }, "optimeDurable" : { "ts" : Timestamp(1608619142, 1), "t" : NumberLong(1) }, "optimeDate" : ISODate("2020-12-22T06:39:02Z"), "optimeDurableDate" : ISODate("2020-12-22T06:39:02Z"), "lastHeartbeat" : ISODate("2020-12-22T06:39:02.935Z"), "lastHeartbeatRecv" : ISODate("2020-12-22T06:39:03.044Z"), "pingMs" : NumberLong(85), "lastHeartbeatMessage" : "", "syncingTo" : "172.16.245.102:27018", "syncSourceHost" : "172.16.245.102:27018", "syncSourceId" : 0, "infoMessage" : "", "configVersion" : 1 }, { "_id" : 2, "name" : "172.16.245.104:27018", #副本3 "health" : 1, "state" : 2, "stateStr" : "SECONDARY", "uptime" : 4052, "optime" : { "ts" : Timestamp(1608619142, 1), "t" : NumberLong(1) }, "optimeDurable" : { "ts" : Timestamp(1608619142, 1), "t" : NumberLong(1) }, "optimeDate" : ISODate("2020-12-22T06:39:02Z"), "optimeDurableDate" : ISODate("2020-12-22T06:39:02Z"), "lastHeartbeat" : ISODate("2020-12-22T06:39:03.368Z"), "lastHeartbeatRecv" : ISODate("2020-12-22T06:39:03.046Z"), "pingMs" : NumberLong(85), "lastHeartbeatMessage" : "", "syncingTo" : "172.16.245.102:27018", "syncSourceHost" : "172.16.245.102:27018", "syncSourceId" : 0, "infoMessage" : "", "configVersion" : 1 } ], "ok" : 1, "operationTime" : Timestamp(1608619142, 1), "$gleStats" : { "lastOpTime" : Timestamp(0, 0), "electionId" : ObjectId("7fffffff0000000000000001") }, "lastCommittedOpTime" : Timestamp(1608619142, 1), "$clusterTime" : { "clusterTime" : Timestamp(1608619142, 1), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } } } configs:PRIMARY>
等几十秒左右,执行上面的命令查看状态,三台机器的配置服务就已形成复制集,其中1台为PRIMARY,其他2台为SECONDARY
5. 分片服务部署
3台服务器执行相同操作
在/data/mongodb/conf目录创建shard1.conf、shard2.conf、shard3.conf,内容如下
[root@node3 conf]# ls config.conf mongos.conf shard1.conf shard2.conf shard3.conf [root@node3 conf]# cat shard1.conf dbpath=/data/mongodb/data/shard1 logpath=/data/mongodb/log/shard1.log/shard1.log port=27001 logappend=true fork=true maxConns=5000 storageEngine=mmapv1 shardsvr=true replSet=shard1 bind_ip=0.0.0.0 [root@node3 conf]# cat shard2.conf dbpath=/data/mongodb/data/shard2 logpath=/data/mongodb/log/shard2.log/shard2.log port=27002 logappend=true fork=true maxConns=5000 storageEngine=mmapv1 shardsvr=true replSet=shard2 bind_ip=0.0.0.0 [root@node3 conf]# cat shard3.conf dbpath=/data/mongodb/data/shard3 logpath=/data/mongodb/log/shard3.log/shard3.log port=27003 logappend=true fork=true maxConns=5000 storageEngine=mmapv1 shardsvr=true replSet=shard3 bind_ip=0.0.0.0
端口分别是27001、27002、27003,分别对应shard1.conf、shard2.conf、shard3.conf
在3台机器的相同端口形成一个分片的复制集,由于3台机器都需要这3个文件,所以根据这9个配置文件分别启动分片服务
三台机器都需要启动分片服务,节点1启动shard1 节点2启动shard1 节点2启动shard1 ….
[root@node3 conf]# /data/mongodb/bin/mongond -f /data/mongodb/conf/shard1.conf [root@node3 conf]# /data/mongodb/bin/mongond -f /data/mongodb/conf/shard2.conf [root@node3 conf]# /data/mongodb/bin/mongond -f /data/mongodb/conf/shard3.conf
6. 将分片配置为复制集
连接mongo,只需在任意一台机器执行即可
mongo --host 172.16.245.103 --port 27001 这里以shard1为例,其他两个分片则再需对应连接到27002、27003的端口进行操作即可
进入数据库admin
use admin
初始化三个分片副本集集群
rs.initiate({_id:"shard1",members:[{_id:0,host:"172.16.245.102:27001"},{_id:1,host:"172.16.245.103:27001"},{_id:2,host:"172.16.245.104:27001"}]}) rs.initiate({_id:"shard2",members:[{_id:0,host:"172.16.245.102:27002"},{_id:1,host:"172.16.245.103:27002"},{_id:2,host:"172.16.245.104:27002"}]}) rs.initiate({_id:"shard3",members:[{_id:0,host:"172.16.245.102:27003"},{_id:1,host:"172.16.245.103:27003"},{_id:2,host:"172.16.245.104:27003"}]})
7. 路由服务部署
3台服务器执行相同操作
在/data/mongodb/conf目录创建mongos.conf,内容如下
[root@node4 conf]# cat mongos.conf logpath=/data/mongodb/log/mongos.log/mongos.log logappend = true port = 27017 fork = true configdb = configs/172.16.245.102:27018,172.16.245.103:27018,172.16.245.104:27018 maxConns=20000 bind_ip=0.0.0.0
启动mongos
分别在三台服务器启动:
[root@node4 conf]# /data/mongodb/bin/mongos -f /data/mongodb/conf/mongos.conf
8. 启动分片功能
连接mongo
mongo --host 172.16.245.102 --port 27017 mongos>use admin
添加分片,只需在一台机器执行即可
mongos>sh.addShard("shard1/172.16.245.102:27001,172.16.245.103:27001,172.16.245.104:27001") mongos>sh.addShard("shard2/172.16.245.102:27002,172.16.245.103:27002,172.16.245.104:27002") mongos>sh.addShard("shard3/172.16.245.102:27003,172.16.245.103:27003,172.16.245.104:27003") mongos> sh.status() --- Sharding Status --- sharding version: { "_id" : 1, "minCompatibleVersion" : 5, "currentVersion" : 6, "clusterId" : ObjectId("5fe184bf29ea91799b557a8b") } shards: { "_id" : "shard1", "host" : "shard1/172.16.245.102:27001,172.16.245.103:27001,172.16.245.104:27001", "state" : 1 } { "_id" : "shard2", "host" : "shard2/172.16.245.102:27002,172.16.245.103:27002,172.16.245.104:27002", "state" : 1 } { "_id" : "shard3", "host" : "shard3/172.16.245.102:27003,172.16.245.103:27003,172.16.245.104:27003", "state" : 1 } active mongoses: "4.0.21" : 3 autosplit: Currently enabled: yes balancer: Currently enabled: yes Currently running: no Failed balancer rounds in last 5 attempts: 0 Migration Results for the last 24 hours: No recent migrations databases: { "_id" : "calon", "primary" : "shard1", "partitioned" : true, "version" : { "uuid" : UUID("2a4780da-8f33-4214-88f8-c9b1a3140299"), "lastMod" : 1 } } { "_id" : "config", "primary" : "config", "partitioned" : true } config.system.sessions shard key: { "_id" : 1 } unique: false balancing: true chunks: shard1 1 { "_id" : { "$minKey" : 1 } } -->> { "_id" : { "$maxKey" : 1 } } on : shard1 Timestamp(1, 0) { "_id" : "test", "primary" : "shard2", "partitioned" : false, "version" : { "uuid" : UUID("d59549a4-3e68-4a7d-baf8-67a4d8372b76"), "lastMod" : 1 } } { "_id" : "ycsb", "primary" : "shard3", "partitioned" : true, "version" : { "uuid" : UUID("6d491868-245e-4c86-a5f5-f8fcd308b45e"), "lastMod" : 1 } } ycsb.usertable shard key: { "_id" : "hashed" } unique: false balancing: true chunks: shard1 2 shard2 2 shard3 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)
9.实现分片功能
设置分片chunk大小
mongos>use config mongos>db.setting.save({"_id":"chunksize","value":1}) #设置块大小为1M是方便实验,不然需要插入海量数据
10. 启用数据库分片并进行测试
mongos> use shardbtest; switched to db shardbtest mongos> mongos> mongos> sh.enableSharding("shardbtest"); { "ok" : 1, "operationTime" : Timestamp(1608620190, 4), "$clusterTime" : { "clusterTime" : Timestamp(1608620190, 4), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } } } mongos> sh.shardCollection("shardbtest.usertable",{"_id":"hashed"}); #为 shardbtest裤中的usertable表进行分片基于id的哈希分片 { "collectionsharded" : "shardbtest.usertable", "collectionUUID" : UUID("2b5a8bcf-6e31-4dac-831f-5fa414253655"), "ok" : 1, "operationTime" : Timestamp(1608620216, 36), "$clusterTime" : { "clusterTime" : Timestamp(1608620216, 36), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } } } mongos> for(i=1;i<=3000;i++){db.usertable.insert({"id":i})} #模拟插入3000条的数据 WriteResult({ "nInserted" : 1 })
11. 查看分片验证
mongos> db.usertable.stats(); { "sharded" : true, "paddingFactorNote" : "paddingFactor is unused and unmaintained in 3.0. It remains hard coded to 1.0 for compatibility only.", "userFlags" : 1, "capped" : false, "ns" : "shardbtest.usertable", "count" : 3000, #总3000 "numExtents" : 9, "size" : 144096, "storageSize" : 516096, "totalIndexSize" : 269808, "indexSizes" : { "_id_" : 122640, "_id_hashed" : 147168 }, "avgObjSize" : 48, "maxSize" : NumberLong(0), "nindexes" : 2, "nchunks" : 6, "shards" : { "shard3" : { "ns" : "shardbtest.usertable", "size" : 48656, "count" : 1013, #shard3写入1013 "avgObjSize" : 48, "numExtents" : 3, "storageSize" : 172032, "lastExtentSize" : 131072, "paddingFactor" : 1, "paddingFactorNote" : "paddingFactor is unused and unmaintained in 3.0. It remains hard coded to 1.0 for compatibility only.", "userFlags" : 1, "capped" : false, "nindexes" : 2, "totalIndexSize" : 89936, "indexSizes" : { "_id_" : 40880, "_id_hashed" : 49056 }, "ok" : 1, "operationTime" : Timestamp(1608620309, 1), "$gleStats" : { "lastOpTime" : { "ts" : Timestamp(1608620272, 38), "t" : NumberLong(1) }, "electionId" : ObjectId("7fffffff0000000000000001") }, "lastCommittedOpTime" : Timestamp(1608620309, 1), "$configServerState" : { "opTime" : { "ts" : Timestamp(1608620307, 1), "t" : NumberLong(1) } }, "$clusterTime" : { "clusterTime" : Timestamp(1608620309, 1), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } } }, "shard2" : { "ns" : "shardbtest.usertable", "size" : 49232, "count" : 1025, #shard2写入1025 "avgObjSize" : 48, "numExtents" : 3, "storageSize" : 172032, "lastExtentSize" : 131072, "paddingFactor" : 1, "paddingFactorNote" : "paddingFactor is unused and unmaintained in 3.0. It remains hard coded to 1.0 for compatibility only.", "userFlags" : 1, "capped" : false, "nindexes" : 2, "totalIndexSize" : 89936, "indexSizes" : { "_id_" : 40880, "_id_hashed" : 49056 }, "ok" : 1, "operationTime" : Timestamp(1608620306, 1), "$gleStats" : { "lastOpTime" : { "ts" : Timestamp(1608620272, 32), "t" : NumberLong(1) }, "electionId" : ObjectId("7fffffff0000000000000001") }, "lastCommittedOpTime" : Timestamp(1608620306, 1), "$configServerState" : { "opTime" : { "ts" : Timestamp(1608620307, 1), "t" : NumberLong(1) } }, "$clusterTime" : { "clusterTime" : Timestamp(1608620309, 1), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } } }, "shard1" : { "ns" : "shardbtest.usertable", "size" : 46208, "count" : 962, #shard1写入962 "avgObjSize" : 48, "numExtents" : 3, "storageSize" : 172032, "lastExtentSize" : 131072, "paddingFactor" : 1, "paddingFactorNote" : "paddingFactor is unused and unmaintained in 3.0. It remains hard coded to 1.0 for compatibility only.", "userFlags" : 1, "capped" : false, "nindexes" : 2, "totalIndexSize" : 89936, "indexSizes" : { "_id_" : 40880, "_id_hashed" : 49056 }, "ok" : 1, "operationTime" : Timestamp(1608620308, 1), "$gleStats" : { "lastOpTime" : { "ts" : Timestamp(1608620292, 10), "t" : NumberLong(1) }, "electionId" : ObjectId("7fffffff0000000000000001") }, "lastCommittedOpTime" : Timestamp(1608620308, 1), "$configServerState" : { "opTime" : { "ts" : Timestamp(1608620307, 1), "t" : NumberLong(1) } }, "$clusterTime" : { "clusterTime" : Timestamp(1608620309, 1), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } } } }, "ok" : 1, "operationTime" : Timestamp(1608620309, 1), "$clusterTime" : { "clusterTime" : Timestamp(1608620309, 1), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } } }
11. 副本节点是否已同步数据
mongos> show dbs admin 0.000GB calon 0.078GB config 0.235GB shardbtest 0.234GB test 0.078GB ycsb 0.234GB mongos> use shardbtest switched to db shardbtest mongos> db.usertable.stats(); { "sharded" : true, "paddingFactorNote" : "paddingFactor is unused and unmaintained in 3.0. It remains hard coded to 1.0 for compatibility only.", "userFlags" : 1, "capped" : false, "ns" : "shardbtest.usertable", "count" : 3000, "numExtents" : 9, "size" : 144096, "storageSize" : 516096, "totalIndexSize" : 269808, "indexSizes" : { "_id_" : 122640, "_id_hashed" : 147168 }, "avgObjSize" : 48, "maxSize" : NumberLong(0), "nindexes" : 2, "nchunks" : 6, "shards" : { "shard2" : { "ns" : "shardbtest.usertable", "size" : 49232, "count" : 1025, "avgObjSize" : 48, "numExtents" : 3, "storageSize" : 172032, "lastExtentSize" : 131072, "paddingFactor" : 1, "paddingFactorNote" : "paddingFactor is unused and unmaintained in 3.0. It remains hard coded to 1.0 for compatibility only.", "userFlags" : 1, "capped" : false, "nindexes" : 2, "totalIndexSize" : 89936, "indexSizes" : { "_id_" : 40880, "_id_hashed" : 49056 }, "ok" : 1, "operationTime" : Timestamp(1608620886, 6), "$gleStats" : { "lastOpTime" : Timestamp(0, 0), "electionId" : ObjectId("7fffffff0000000000000001") }, "lastCommittedOpTime" : Timestamp(1608620886, 6), "$configServerState" : { "opTime" : { "ts" : Timestamp(1608620888, 1), "t" : NumberLong(1) } }, "$clusterTime" : { "clusterTime" : Timestamp(1608620888, 1), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } } }, "shard3" : { "ns" : "shardbtest.usertable", "size" : 48656, "count" : 1013, "avgObjSize" : 48, "numExtents" : 3, "storageSize" : 172032, "lastExtentSize" : 131072, "paddingFactor" : 1, "paddingFactorNote" : "paddingFactor is unused and unmaintained in 3.0. It remains hard coded to 1.0 for compatibility only.", "userFlags" : 1, "capped" : false, "nindexes" : 2, "totalIndexSize" : 89936, "indexSizes" : { "_id_" : 40880, "_id_hashed" : 49056 }, "ok" : 1, "operationTime" : Timestamp(1608620889, 1), "$gleStats" : { "lastOpTime" : Timestamp(0, 0), "electionId" : ObjectId("7fffffff0000000000000001") }, "lastCommittedOpTime" : Timestamp(1608620889, 1), "$configServerState" : { "opTime" : { "ts" : Timestamp(1608620888, 1), "t" : NumberLong(1) } }, "$clusterTime" : { "clusterTime" : Timestamp(1608620889, 1), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } } }, "shard1" : { "ns" : "shardbtest.usertable", "size" : 46208, "count" : 962, "avgObjSize" : 48, "numExtents" : 3, "storageSize" : 172032, "lastExtentSize" : 131072, "paddingFactor" : 1, "paddingFactorNote" : "paddingFactor is unused and unmaintained in 3.0. It remains hard coded to 1.0 for compatibility only.", "userFlags" : 1, "capped" : false, "nindexes" : 2, "totalIndexSize" : 89936, "indexSizes" : { "_id_" : 40880, "_id_hashed" : 49056 }, "ok" : 1, "operationTime" : Timestamp(1608620888, 1), "$gleStats" : { "lastOpTime" : Timestamp(0, 0), "electionId" : ObjectId("7fffffff0000000000000001") }, "lastCommittedOpTime" : Timestamp(1608620888, 1), "$configServerState" : { "opTime" : { "ts" : Timestamp(1608620888, 1), "t" : NumberLong(1) } }, "$clusterTime" : { "clusterTime" : Timestamp(1608620888, 1), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } } } }, "ok" : 1, "operationTime" : Timestamp(1608620889, 1), "$clusterTime" : { "clusterTime" : Timestamp(1608620889, 1), "signature" : { "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="), "keyId" : NumberLong(0) } } } mongos>
以上就实现了mongodb复制集的高可用以及分片