MongoDB sharded cluster setup

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1. config server replicaset 설정

각 인스턴스에 아래의 명령어로 config server 실행

• mongod --configsvr --replSet replconfig --dbpath /var/lib/mongodb/configsvr -port 20001 --wiredTigerCacheSizeGB 2.0 --bind_ip 0.0.0.0 --fork --logpath /var/log/mongodb/configsvr.log
• mongod --configsvr --replSet replconfig --dbpath /var/lib/mongodb/configsvr -port 20001 --wiredTigerCacheSizeGB 2.0 --bind_ip 0.0.0.0 --fork --logpath /var/log/mongodb/configsvr.log
• mongod --configsvr --replSet replconfig --dbpath /var/lib/mongodb/configsvr -port 20001 --wiredTigerCacheSizeGB 2.0 --bind_ip 0.0.0.0 --fork --logpath /var/log/mongodb/configsvr.log

레플리카 셋 설정

(config server로 설정한 것 중 한곳에 접속만하여 설정하면 된다) mongo --host 192.168.0.101 --port 20001

rs.initiate(
  {
    _id: "replconfig",
    configsvr: true,
    members: [
      { _id : 0, host : "192.168.0.101:20001" },
      { _id : 1, host : "192.168.0.102:20001" },
      { _id : 2, host : "192.168.0.103:20001" }
    ]
  }
)

2. shard replicaset 설정

• mongod --shardsvr --replSet shard1repl --dbpath /var/lib/mongodb/shard1 -port 20002 --wiredTigerCacheSizeGB 4.0 --bind_ip 0.0.0.0 --fork --logpath /var/log/mongodb/shard1.log
• mongod --shardsvr --replSet shard1repl --dbpath /var/lib/mongodb/shard1 -port 20002 --wiredTigerCacheSizeGB 4.0 --bind_ip 0.0.0.0 --fork --logpath /var/log/mongodb/shard1.log
• mongod --shardsvr --replSet shard1repl --dbpath /var/lib/mongodb/shard1 -port 20002 --wiredTigerCacheSizeGB 4.0 --bind_ip 0.0.0.0 --fork --logpath /var/log/mongodb/shard1.log

(shard replicaset 설정한 것 중 한곳에 접속만하여 설정하면 된다) mongo --host 192.168.0.101 --port 20002

rs.initiate(
  {
    _id: "shard1repl",
    members: [
      { _id : 0, host : "192.168.0.101:20002" },
      { _id : 1, host : "192.168.0.102:20002" },
      { _id : 2, host : "192.168.0.103:20002" }
    ]
  }
)

3. mongos 설정

config server가 돌아가는 곳에 모두 query router 인 mongos를 동작시킨다. 여러 mongos를 각 디비 서버에 가지는것이 고가용성과 확장성에 좋으며 어플리케이션과 라우터사이의 네트워크 지연을 줄일 수 있다.

• mongos --configdb replconfig/192.168.0.101:20001,192.168.0.102:20001,192.168.0.103:20001 --bind_ip 0.0.0.0 --fork --logpath /var/log/mongodb/queryrouter.log
• mongos --configdb replconfig/192.168.0.101:20001,192.168.0.102:20001,192.168.0.103:20001 --bind_ip 0.0.0.0 --fork --logpath /var/log/mongodb/queryrouter.log
• mongos --configdb replconfig/192.168.0.101:20001,192.168.0.102:20001,192.168.0.103:20001 --bind_ip 0.0.0.0 --fork --logpath /var/log/mongodb/queryrouter.log

4. shard를 mongos에 등록

• sh.addShard( "shard1repl/192.168.0.101:20002,192.168.0.102:20002,192.168.0.103:20002")

5. user 등록

$ mongo

> mongos
> use admin
> db.createUser({
  user: 'username',
  pwd: 'password',
  roles: ['root']
})

> db.getUsers()

6. auth 모드로 config server 다시 실행

왜 configserver 만 auth 모드로하는가? 생성한 유저는 config server의 데이터에 저장되기때문에 shard 서버에 들어가서 db.getUsers()확인해보면 존재하지 않는다. https://www.mydbaworld.com/how-authentication-works-shared-mongodb-cluster/

• mongod --configsvr --replSet replconfig --auth --dbpath /var/lib/mongodb/configsvr -port 20001 --wiredTigerCacheSizeGB 2.0 --bind_ip 0.0.0.0 --fork --logpath /var/log/mongodb/configsvr.log
• mongod --configsvr --replSet replconfig --auth --dbpath /var/lib/mongodb/configsvr -port 20001 --wiredTigerCacheSizeGB 2.0 --bind_ip 0.0.0.0 --fork --logpath /var/log/mongodb/configsvr.log
• mongod --configsvr --replSet replconfig --auth --dbpath /var/lib/mongodb/configsvr -port 20001 --wiredTigerCacheSizeGB 2.0 --bind_ip 0.0.0.0 --fork --logpath /var/log/mongodb/configsvr.log

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Error case

• Failed to unlink socket file /tmp/mongodb-20002.sock Operation not permitted

  • sudo rm -rf /tmp/mongodb-20002.sock 로 해당파일 삭제 후 재실행

• NonExistentPath: Data directory /var/lib/mongodb/configsvr not found. Create the missing directory or specify another path using (1) the --dbpath command line option, or (2) by adding the 'storage.dbPath' option in the configuration file., terminating

  • 파일및 경로 생성 후 권한부여 sudo chown -R $USER:$USER path

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참고

• https://docs.mongodb.com/manual/tutorial/deploy-shard-cluster/
• https://docs.ncloud.com/ko/database/database-10-3.html
• https://www.howtoforge.com/tutorial/deploying-mongodb-sharded-cluster-on-centos-7/
• https://kslee7746.tistory.com/entry/MongoDB-Sharding%EC%83%A4%EB%94%A9