Docker: Mongo Cluster Kurulumu

4 min readDec 4, 2022

version: '3'

services:
    mongodb1:
        image: mongo:4
        restart: always
        container_name: mongodb1
        volumes:
        - mongodata1:/data/db
        expose:
        - "27017"
        entrypoint: [ "/usr/bin/mongod", "--replSet", "rsmongo", "--bind_ip_all"]

    mongodb2:
        image: mongo:4
        restart: always
        container_name: mongodb2
        volumes:
        - mongodata2:/data/db
        expose:
        - "27017"
        entrypoint: [ "/usr/bin/mongod", "--replSet", "rsmongo", "--bind_ip_all"]

    mongodb3:
        image: mongo:4
        restart: always
        container_name: mongodb3
        volumes:
        - mongodata3:/data/db
        expose:
        - "27017"
        entrypoint: [ "/usr/bin/mongod", "--replSet", "rsmongo", "--bind_ip_all" ]

volumes:
    mongodata1:
    mongodata2:
    mongodata3:

Yukarıdaki docker-compose.yaml dosyasını aşağıdaki komut ile up duruma getiriyoruz.

docker-compose up -d

Aşağıdaki komut ile containerları kontrol ediyoruz,

docker ps

CONTAINER ID   IMAGE       COMMAND                  CREATED         STATUS         PORTS        NAMES
7e4e96cde9f4   mongo:4     "/usr/bin/mongod --r…"   5 minutes ago   Up 2 minutes   27017/tcp    mongodb2
673c26d5e0e0   mongo:4     "/usr/bin/mongod --r…"   5 minutes ago   Up 2 minutes   27017/tcp    mongodb3
b7253224ed72   mongo:4     "/usr/bin/mongod --r…"   5 minutes ago   Up 2 minutes   27017/tcp    mongodb1

Aşağıdaki komut ile mongodb1 container’da mongo komutu çalıştırıp, mongo shell’e bağlanıyoruz.

docker-compose exec mongodb1 mongo

Açılan shell ‘de aşağıdaki konfigürasyon parametrelerini giriyoruz. Burada mongo cluster üyelerini(containerları) tanımlıyoruz.

rsconf = {
   _id : "rsmongo",
   members: [
       {
           "_id": 0,
           "host": "mongodb1:27017",
           "priority": 4
       },
       {
           "_id": 1,
           "host": "mongodb2:27017",
           "priority": 2
       },
       {
           "_id": 2,
           "host": "mongodb3:27017",
           "priority": 1
       }
   ]
}

Yukarıdaki ayarlamaları yaptıktan sonra, Cluster’ı başlatmak için aşağıdaki komutu giriyoruz.

rs.initiate(rsconf);

Artık cluster devrede, İşlemler tamamlandı. Aşağıdaki komut ile nodeların durumunu görebiliriz.

rs.status()

root@ubuntu-1:/home/onur/mongo-docker-compose# docker-compose exec mongodb1 mongo
MongoDB shell version v4.4.18
connecting to: mongodb://127.0.0.1:27017/?compressors=disabled&gssapiServiceName=mongodb
Implicit session: session { "id" : UUID("dcfc2ae6-de43-45e6-b91f-f3be339535b5") }
MongoDB server version: 4.4.18
---
The server generated these startup warnings when booting:
        2022-12-04T17:32:02.574+00:00: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine. See http://dochub.mongodb.org/core/prodnotes-filesystem
        2022-12-04T17:32:04.156+00:00: Access control is not enabled for the database. Read and write access to data and configuration is unrestricted
        2022-12-04T17:32:04.156+00:00: You are running this process as the root user, which is not recommended
---
---
        Enable MongoDB's free cloud-based monitoring service, which will then receive and display
        metrics about your deployment (disk utilization, CPU, operation statistics, etc).

        The monitoring data will be available on a MongoDB website with a unique URL accessible to you
        and anyone you share the URL with. MongoDB may use this information to make product
        improvements and to suggest MongoDB products and deployment options to you.

        To enable free monitoring, run the following command: db.enableFreeMonitoring()
        To permanently disable this reminder, run the following command: db.disableFreeMonitoring()
---
rsmongo:PRIMARY> rs.status()
{
 "set" : "rsmongo",
 "date" : ISODate("2022-12-04T17:44:15.259Z"),
 "myState" : 1,
 "term" : NumberLong(3),
 "syncSourceHost" : "",
 "syncSourceId" : -1,
 "heartbeatIntervalMillis" : NumberLong(2000),
 "majorityVoteCount" : 2,
 "writeMajorityCount" : 2,
 "votingMembersCount" : 3,
 "writableVotingMembersCount" : 3,
 "optimes" : {
  "lastCommittedOpTime" : {
   "ts" : Timestamp(1670175854, 1),
   "t" : NumberLong(3)
  },
  "lastCommittedWallTime" : ISODate("2022-12-04T17:44:14.393Z"),
  "readConcernMajorityOpTime" : {
   "ts" : Timestamp(1670175854, 1),
   "t" : NumberLong(3)
  },
  "readConcernMajorityWallTime" : ISODate("2022-12-04T17:44:14.393Z"),
  "appliedOpTime" : {
   "ts" : Timestamp(1670175854, 1),
   "t" : NumberLong(3)
  },
  "durableOpTime" : {
   "ts" : Timestamp(1670175854, 1),
   "t" : NumberLong(3)
  },
  "lastAppliedWallTime" : ISODate("2022-12-04T17:44:14.393Z"),
  "lastDurableWallTime" : ISODate("2022-12-04T17:44:14.393Z")
 },
 "lastStableRecoveryTimestamp" : Timestamp(1670175834, 1),
 "electionCandidateMetrics" : {
  "lastElectionReason" : "electionTimeout",
  "lastElectionDate" : ISODate("2022-12-04T17:32:14.348Z"),
  "electionTerm" : NumberLong(3),
  "lastCommittedOpTimeAtElection" : {
   "ts" : Timestamp(0, 0),
   "t" : NumberLong(-1)
  },
  "lastSeenOpTimeAtElection" : {
   "ts" : Timestamp(1670175116, 1),
   "t" : NumberLong(2)
  },
  "numVotesNeeded" : 2,
  "priorityAtElection" : 4,
  "electionTimeoutMillis" : NumberLong(10000),
  "numCatchUpOps" : NumberLong(0),
  "newTermStartDate" : ISODate("2022-12-04T17:32:14.363Z"),
  "wMajorityWriteAvailabilityDate" : ISODate("2022-12-04T17:32:14.880Z")
 },
 "members" : [
  {
   "_id" : 0,
   "name" : "mongodb1:27017",
   "health" : 1,
   "state" : 1,
   "stateStr" : "PRIMARY",
   "uptime" : 733,
   "optime" : {
    "ts" : Timestamp(1670175854, 1),
    "t" : NumberLong(3)
   },
   "optimeDate" : ISODate("2022-12-04T17:44:14Z"),
   "lastAppliedWallTime" : ISODate("2022-12-04T17:44:14.393Z"),
   "lastDurableWallTime" : ISODate("2022-12-04T17:44:14.393Z"),
   "syncSourceHost" : "",
   "syncSourceId" : -1,
   "infoMessage" : "",
   "electionTime" : Timestamp(1670175134, 1),
   "electionDate" : ISODate("2022-12-04T17:32:14Z"),
   "configVersion" : 1,
   "configTerm" : 3,
   "self" : true,
   "lastHeartbeatMessage" : ""
  },
  {
   "_id" : 1,
   "name" : "mongodb2:27017",
   "health" : 1,
   "state" : 2,
   "stateStr" : "SECONDARY",
   "uptime" : 730,
   "optime" : {
    "ts" : Timestamp(1670175854, 1),
    "t" : NumberLong(3)
   },
   "optimeDurable" : {
    "ts" : Timestamp(1670175854, 1),
    "t" : NumberLong(3)
   },
   "optimeDate" : ISODate("2022-12-04T17:44:14Z"),
   "optimeDurableDate" : ISODate("2022-12-04T17:44:14Z"),
   "lastAppliedWallTime" : ISODate("2022-12-04T17:44:14.393Z"),
   "lastDurableWallTime" : ISODate("2022-12-04T17:44:14.393Z"),
   "lastHeartbeat" : ISODate("2022-12-04T17:44:14.570Z"),
   "lastHeartbeatRecv" : ISODate("2022-12-04T17:44:13.567Z"),
   "pingMs" : NumberLong(0),
   "lastHeartbeatMessage" : "",
   "syncSourceHost" : "mongodb1:27017",
   "syncSourceId" : 0,
   "infoMessage" : "",
   "configVersion" : 1,
   "configTerm" : 3
  },
  {
   "_id" : 2,
   "name" : "mongodb3:27017",
   "health" : 1,
   "state" : 2,
   "stateStr" : "SECONDARY",
   "uptime" : 730,
   "optime" : {
    "ts" : Timestamp(1670175854, 1),
    "t" : NumberLong(3)
   },
   "optimeDurable" : {
    "ts" : Timestamp(1670175854, 1),
    "t" : NumberLong(3)
   },
   "optimeDate" : ISODate("2022-12-04T17:44:14Z"),
   "optimeDurableDate" : ISODate("2022-12-04T17:44:14Z"),
   "lastAppliedWallTime" : ISODate("2022-12-04T17:44:14.393Z"),
   "lastDurableWallTime" : ISODate("2022-12-04T17:44:14.393Z"),
   "lastHeartbeat" : ISODate("2022-12-04T17:44:14.569Z"),
   "lastHeartbeatRecv" : ISODate("2022-12-04T17:44:15.078Z"),
   "pingMs" : NumberLong(0),
   "lastHeartbeatMessage" : "",
   "syncSourceHost" : "mongodb1:27017",
   "syncSourceId" : 0,
   "infoMessage" : "",
   "configVersion" : 1,
   "configTerm" : 3
  }
 ],
 "ok" : 1,
 "$clusterTime" : {
  "clusterTime" : Timestamp(1670175854, 1),
  "signature" : {
   "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
   "keyId" : NumberLong(0)
  }
 },
 "operationTime" : Timestamp(1670175854, 1)
}

rs.conf komutu ilede cluster hakkında bilgi alabiliriz;

rsmongo:PRIMARY> rs.conf()
{
 "_id" : "rsmongo",
 "version" : 1,
 "term" : 3,
 "protocolVersion" : NumberLong(1),
 "writeConcernMajorityJournalDefault" : true,
 "members" : [
  {
   "_id" : 0,
   "host" : "mongodb1:27017",
   "arbiterOnly" : false,
   "buildIndexes" : true,
   "hidden" : false,
   "priority" : 4,
   "tags" : {

   },
   "slaveDelay" : NumberLong(0),
   "votes" : 1
  },
  {
   "_id" : 1,
   "host" : "mongodb2:27017",
   "arbiterOnly" : false,
   "buildIndexes" : true,
   "hidden" : false,
   "priority" : 2,
   "tags" : {

   },
   "slaveDelay" : NumberLong(0),
   "votes" : 1
  },
  {
   "_id" : 2,
   "host" : "mongodb3:27017",
   "arbiterOnly" : false,
   "buildIndexes" : true,
   "hidden" : false,
   "priority" : 1,
   "tags" : {

   },
   "slaveDelay" : NumberLong(0),
   "votes" : 1
  }
 ],
 "settings" : {
  "chainingAllowed" : true,
  "heartbeatIntervalMillis" : 2000,
  "heartbeatTimeoutSecs" : 10,
  "electionTimeoutMillis" : 10000,
  "catchUpTimeoutMillis" : -1,
  "catchUpTakeoverDelayMillis" : 30000,
  "getLastErrorModes" : {

  },
  "getLastErrorDefaults" : {
   "w" : 1,
   "wtimeout" : 0
  },
  "replicaSetId" : ObjectId("638cd91c0188bc7bb7858f81")
 }
}