1、mongodb部署replicasets副本集实现高可用解决方案详细过程NoSQL的产生就是为了解决大数据量、高扩展性、高性能、灵活数据模型、高可用性。但是光通过主从模式的架构远远达不到上面几点，由此MongoDB设计了副本集和分片的功能，先来用用副本集：1，设置yum源安装创建/etc/yum.repos.d/mongodb-enterprise.repo文件，这样就可以使用yum来安装mongodb了。mongodb-org-3.0name=MongoDB Repositorybaseurl=https:/repo.mongodb.org/yum/redhat/$releasever/mo
2、ngodb-org/3.0/x86_64/gpgcheck=1enabled=1gpgkey=https:/www.mongodb.org/static/pgp/server-3.0.asc每一个release版本的.repo文件可以在repository找到，记住奇数镜像版本（比如e.g.2.5）是开发版本，放在生成环境是不太合适的。2，源码安装2.1 下载安装包在官方网站可以下载到比较新的版本，下载地址：https:/www.mongodb.org/dr/fastdl.mongodb.org/linux/mongodb-linux-x86_64-3.2.3.tgz/download；我这里
3、下载的是稳定版本：mongodb-linux-x86_64-3.0.3.tgz，安装也是用的3.0.3； 3.0.3的下载地址为：2.2 解压安装tar -xvf mongodb-linux-x86_64-3.0.3.tgz -C /usr/local/3 启动3个mongodb服务安装mongodb replica sets，至少需要3台linux服务器，而初始化副本集合，本来应该是3台服务器，但是这里只是测试环境，启用了3个mongodb端口进程来来模拟3个mongodb的服务器达到一样的效果，在实际中，可以部署在多台mongodb服务器上，如下表所示：Mongodb 主机服务器端口地址默
4、认角色mongodb主机 1localhost:27017primarymongodb主机 2localhost:27018secondarymongodb主机 3localhost:27019secondary开始启动3个mongodb服务：# 启动第一个mongodb 27017，默认为primary服务器mkdir -p /data/mongodb/log27017mkdir -p /data/mongodb/data27017/usr/local/mongodb-linux-x86_64-3.0.3/bin/mongod -replSet repset -port 27017 -dbp
5、ath /data/mongodb/data27017 -oplogSize 2048 -logpath /data/mongodb/log27017/mongod.log &# 启动第二个mongodb 27018mkdir -p /data/mongodb/log27018mkdir -p /data/mongodb/data27018/usr/local/mongodb-linux-x86_64-3.0.3/bin/mongod -replSet repset -port 27018 -dbpath /data/mongodb/data27018 -oplogSize 2048 -log
6、path /data/mongodb/log27018/mongod.log &# 启动第三个 mongodb 27019mkdir -p /data/mongodb/log27019mkdir -p /data/mongodb/data27019/usr/local/mongodb-linux-x86_64-3.0.3/bin/mongod -replSet repset -port 27019 -dbpath /data/mongodb/data27019 -oplogSize 2048 -logpath /data/mongodb/log27019/mongod.log &4 添加rep
7、lica sets配置在任何一台mongodb实例上登录，进入admin库，执行config命令： use adminswitched to db admin config = _id:repset, members:. _id:0,host:mongodb_server:27017,. _id:1,host:mongodb_server:27018,. _id:2,host:mongodb_server:27019. ; config = _id:repset, members:. . _id:0,host:mongodb_server:27017,. . _id:1,host:mongod
8、b_server:27018,. . _id:2,host:mongodb_server:27019. . ; _id : repset, members : _id : 0, host : mongodb_server:27017 , _id : 1, host : mongodb_server:27018 , _id : 2, host : mongodb_server:27019 5 初始化副本集# 初始化副本集配置，使用rs.initiate(config);命令rs.initiate(config); rs.initiate(config); ok : 1 repset:SECOND
9、ARY6 查看replica sets状态看到config配置里面的第一个默认为primary，后面的都为secondary，然后查看optime : Timestamp(1465641737, 1)，如果集合中的mongodb的optime一致，表是集群中各个mongodb数据是保持一致性的：# 随意登录一个mongodb服务rootoracle_master # /usr/local/mongodb-linux-x86_64-3.0.3/bin/mongo localhost:27017MongoDB shell version: 3.0.3connecting to: localhost
10、:27017/testServer has startup warnings: 2016-06-10T07:56:33.333-0700 I CONTROL initandlisten * WARNING: You are running this process as the root user, which is not recommended.2016-06-10T07:56:33.333-0700 I CONTROL initandlisten repset:PRIMARY use adminswitched to db adminrepset:PRIMARY # 查看状态如下：rep
11、set:PRIMARY rs.status(); set : repset, date : ISODate(2016-06-10T15:04:54.045Z), myState : 1, members : _id : 0, name : mongodb_server:27017, health : 1, state : 1, stateStr : PRIMARY, uptime : 501, optime : Timestamp(1465571046, 1), optimeDate : ISODate(2016-06-10T15:04:06Z), electionTime : Timesta
12、mp(1465571050, 1), electionDate : ISODate(2016-06-10T15:04:10Z), configVersion : 1, self : true , _id : 1, name : mongodb_server:27018, health : 1, state : 2, stateStr : SECONDARY, uptime : 47, optime : Timestamp(1465571046, 1), optimeDate : ISODate(2016-06-10T15:04:06Z), lastHeartbeat : ISODate(201
13、6-06-10T15:04:52.493Z), lastHeartbeatRecv : ISODate(2016-06-10T15:04:52.612Z), pingMs : 1, configVersion : 1 , _id : 2, name : mongodb_server:27019, health : 1, state : 2, stateStr : SECONDARY, uptime : 47, optime : Timestamp(1465571046, 1), optimeDate : ISODate(2016-06-10T15:04:06Z), lastHeartbeat
14、: ISODate(2016-06-10T15:04:52.642Z), lastHeartbeatRecv : ISODate(2016-06-10T15:04:52.642Z), pingMs : 0, lastHeartbeatMessage : could not find member to sync from, configVersion : 1 , ok : 1repset:PRIMARY7，查看后台日志可以看到27107的mongodb默认成为了primary，而27018和27019的成为了secondary了：rootoracle_master # tail -f /dat
15、a/mongodb/log27017/mongod.log2016-06-11T03:42:19.664-0700 I REPL ReplicationExecutor replSet election succeeded, assuming primary role2016-06-11T03:42:19.664-0700 I REPL ReplicationExecutor transition to PRIMARY2016-06-11T03:42:19.686-0700 I REPL ReplicationExecutor Member mongodb_server:27019 is no
16、w in state STARTUP22016-06-11T03:42:19.738-0700 I REPL rsSync transition to primary complete; database writes are now permitted2016-06-11T03:42:22.798-0700 I NETWORK initandlisten connection accepted from 192.168.136.128:18197 #6 (4 connections now open)2016-06-11T03:42:22.812-0700 I NETWORK initand
17、listen connection accepted from 192.168.136.128:18198 #7 (5 connections now open)2016-06-11T03:42:22.849-0700 I NETWORK conn6 end connection 192.168.136.128:18197 (4 connections now open)2016-06-11T03:42:22.906-0700 I NETWORK conn7 end connection 192.168.136.128:18198 (3 connections now open)2016-06
18、-11T03:42:23.668-0700 I REPL ReplicationExecutor Member mongodb_server:27018 is now in state SECONDARY2016-06-11T03:42:23.689-0700 I REPL ReplicationExecutor Member mongodb_server:27019 is now in state SECONDARY8，验证replica sets 数据一致性（1）先进去主库primary的mongodb上，录入数据：# 登录primary主库rootoracle_master mongod
19、b# /usr/local/mongodb-linux-x86_64-3.0.3/bin/mongo localhost:27017MongoDB shell version: 3.0.3connecting to: localhost:27017/testServer has startup warnings: 2016-06-11T03:41:07.938-0700 I CONTROL initandlisten * WARNING: You are running this process as the root user, which is not recommended.2016-0
20、6-11T03:41:07.938-0700 I CONTROL initandlisten repset:PRIMARY# 录入数据repset:PRIMARY use yes_db;switched to db yes_dbrepset:PRIMARY db.yes_users.insert(uid:20160611_0001,uname:tim.man);WriteResult( nInserted : 1 )repset:PRIMARY（2）去第一个备库27018上，验证数据，有了yes_users表的数据，如下：rootoracle_master mongodb# /usr/loca
21、l/mongodb-linux-x86_64-3.0.3/bin/mongo localhost:27018MongoDB shell version: 3.0.3connecting to: localhost:27018/testServer has startup warnings: 2016-06-11T03:41:14.305-0700 I CONTROL initandlisten * WARNING: You are running this process as the root user, which is not recommended.2016-06-11T03:41:1
22、4.305-0700 I CONTROL initandlisten repset:SECONDARY use yes_db;switched to db yes_dbrepset:SECONDARY show tables;2016-06-11T04:03:02.088-0700 E QUERY Error: listCollections failed: note : from execCommand, ok : 0, errmsg : not master at Error () at DB._getCollectionInfosCommand (src/mongo/shell/db.j
23、s:646:15) at DB.getCollectionInfos (src/mongo/shell/db.js:658:20) at DB.getCollectionNames (src/mongo/shell/db.js:669:17) at shellHelper.show (src/mongo/shell/utils.js:625:12) at shellHelper (src/mongo/shell/utils.js:524:36)at (shellhelp2):1:1 at src/mongo/shell/db.js:646# mongodb默认是从主节点读写数据的，副本节点上不
24、允许读，需要设置副本节点可以读。repset:SECONDARY db.getMongo().setSlaveOk();repset:SECONDARY show tables;system.indexesyes_usersrepset:SECONDARY db.yes_users.find(); # 看到有数据了 _id : ObjectId(575bef8126150b8de92029eb), uid : 20160611_0001 repset:SECONDARY（3）去第二个secondary备库27019上，检查数据是否已经复制过来：rootoracle_master mongodb
25、# /usr/local/mongodb-linux-x86_64-3.0.3/bin/mongo localhost:27019MongoDB shell version: 3.0.3connecting to: localhost:27019/testServer has startup warnings: 2016-06-11T03:41:20.363-0700 I CONTROL initandlisten * WARNING: You are running this process as the root user, which is not recommended.2016-06
26、-11T03:41:20.363-0700 I CONTROL initandlisten repset:SECONDARY use yes_dbswitched to db yes_dbrepset:SECONDARY db.getMongo().setSlaveOk();# mongodb默认是从主节点读写数据的，副本节点上不允许读，需要设置副本节点可以读。repset:SECONDARY db.yes_users.find();# 看到有数据了，数据已经复制过来。 _id : ObjectId(575bef8126150b8de92029eb), uid : 20160611_0001
27、repset:SECONDARY9，验证primary、secondary自动切换9.1 自动切换示意图官方介绍： Replica Set High AvailabilityReplica sets provide high availability using automatic failover. Failover allows a secondary member to become primary if the current primary becomes unavailable.9.2 验证自动切换操作当primary不可用，则自动将合适的secondary成员切换成新的prima
28、ry，接下来的(1) - (5)就来验证这个：（1） 关闭27017的mongod服务，即停止primary主库：rootoracle_master mongodb# /usr/local/mongodb-linux-x86_64-3.0.3/bin/mongo localhost:27017MongoDB shell version: 3.0.3connecting to: localhost:27017/testServer has startup warnings: 2016-06-11T03:41:07.938-0700 I CONTROL initandlisten * WARNIN
29、G: You are running this process as the root user, which is not recommended.2016-06-11T03:41:07.938-0700 I CONTROL initandlisten repset:PRIMARY use adminswitched to db adminrepset:PRIMARY db.shutdownServer();2016-06-11T04:18:24.148-0700 I NETWORK DBClientCursor:init call() failedserver should be down.2016-06-11T04:18:24.151-0700 I NETWORK trying reconnect to localhost:27017 (127.0.0.1) failed2016-06-11T04:18:24.152-0700 I NETWORK reconnect localhost:27017 (127.0.0.1
