node.jsmongodbmongoose

ReplicaSetNoPrimary MongooseServerSelectionError: getaddrinfo EAI_AGAIN mongodb-primary


I have setup a mongodb replicaset in docker. When i connect to the mongodb using cli, it works fine. However attempting to connect to it via node.js with the use of mongoose package gives the following error message.

MongooseServerSelectionError: getaddrinfo EAI_AGAIN mongodb-primary at NativeConnection.Connection.openUri (/home/kay/checkpoint/stream-hatchet/node_modules/mongoose/lib/connection.js:800:32) at /home/kay/checkpoint/stream-hatchet/node_modules/mongoose/lib/index.js:341:10 at /home/kay/checkpoint/stream-hatchet/node_modules/mongoose/lib/helpers/promiseOrCallback.js:31:5 at new Promise () at promiseOrCallback (/home/kay/checkpoint/stream-hatchet/node_modules/mongoose/lib/helpers/promiseOrCallback.js:30:10) at Mongoose.connect (/home/kay/checkpoint/stream-hatchet/node_modules/mongoose/lib/index.js:340:10) at Object.MongoDBService [as default] (/home/kay/checkpoint/stream-hatchet/src/services/mongodb.service.ts:20:24) at Streaming (/home/kay/checkpoint/stream-hatchet/src/main.ts:16:29) at Object. (/home/kay/checkpoint/stream-hatchet/src/main.ts:38:1) at Module._compile (internal/modules/cjs/loader.js:1137:30) at Module.m._compile (/home/kay/checkpoint/stream-hatchet/node_modules/ts-node/src/index.ts:858:23) at Module._extensions..js (internal/modules/cjs/loader.js:1157:10) at Object.require.extensions. [as .ts] (/home/kay/checkpoint/stream-hatchet/node_modules/ts-node/src/index.ts:861:12) at Module.load (internal/modules/cjs/loader.js:985:32) at Function.Module._load (internal/modules/cjs/loader.js:878:14) at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:71:12) { reason: TopologyDescription { type: 'ReplicaSetNoPrimary', setName: 'replicaset', maxSetVersion: 61323, maxElectionId: 7fffffff0000000000000002, servers: Map { 'mongodb-primary:27017' => [ServerDescription], 'mongodb-arbiter:27017' => [ServerDescription] }, stale: false, compatible: true, compatibilityError: null, logicalSessionTimeoutMinutes: null, heartbeatFrequencyMS: 10000, localThresholdMS: 15, commonWireVersion: 9 } }

{ reason: TopologyDescription { type: 'ReplicaSetNoPrimary', setName: 'replicaset', maxSetVersion: 61323, maxElectionId: 7fffffff0000000000000002, servers: Map { 'mongodb-primary:27017' => [ServerDescription], 'mongodb-arbiter:27017' => [ServerDescription] }, stale: false, compatible: true, compatibilityError: null, logicalSessionTimeoutMinutes: null, heartbeatFrequencyMS: 10000, localThresholdMS: 15, commonWireVersion: 9 } }

nodejs

import mongoose from "mongoose";

const MongoDBService = async () => {

    try {

        const connectionString = "mongodb://root:password123@localhost:27017/streamhatchet?authSource=admin&replicaSet=replicaset&retryWrites=true"

        const options = {
          useNewUrlParser: true,
          useUnifiedTopology: true,
          useCreateIndex: true,
          useFindAndModify: false,
          autoIndex: true,
          poolSize: 10,
          serverSelectionTimeoutMS: 30000,
          socketTimeoutMS: 75000,
          family: 4,
          keepAlive: true, 
          keepAliveInitialDelay: 300000,
        };

        await mongoose.connect(connectionString, options);

    } catch (error) {
        console.log(error);
    }

    mongoose.connection.on("error", (err) => {
       console.log(error);
    });
};


export default MongoDBService;

docker-compose.yml;

version: '2'

services:
  mongodb-primary:
    image: 'docker.io/bitnami/mongodb:4.4-debian-10'
    ports:
      - 27017:27017
    environment:
      - MONGODB_ADVERTISED_HOSTNAME=mongodb-primary
      - MONGODB_REPLICA_SET_MODE=primary
      - MONGODB_ROOT_PASSWORD=password123
      - MONGODB_REPLICA_SET_KEY=replicasetkey123
    volumes:
      - 'mongodb_master_data:/bitnami/mongodb'

  mongodb-arbiter:
    image: 'docker.io/bitnami/mongodb:4.4-debian-10'
    depends_on:
      - mongodb-primary
    environment:
      - MONGODB_ADVERTISED_HOSTNAME=mongodb-arbiter
      - MONGODB_REPLICA_SET_MODE=arbiter
      - MONGODB_INITIAL_PRIMARY_HOST=mongodb-primary
      - MONGODB_INITIAL_PRIMARY_ROOT_PASSWORD=password123
      - MONGODB_REPLICA_SET_KEY=replicasetkey123

volumes:
  mongodb_master_data:
    driver: local
mongo --host localhost --port 27017 --username root --password password123 admin

rs.status()

replicaset:PRIMARY> rs.status()
{
    "set" : "replicaset",
    "date" : ISODate("2020-11-19T09:36:25.442Z"),
    "myState" : 1,
    "term" : NumberLong(2),
    "syncSourceHost" : "",
    "syncSourceId" : -1,
    "heartbeatIntervalMillis" : NumberLong(2000),
    "majorityVoteCount" : 2,
    "writeMajorityCount" : 1,
    "votingMembersCount" : 2,
    "writableVotingMembersCount" : 1,
    "optimes" : {
        "lastCommittedOpTime" : {
            "ts" : Timestamp(1605778584, 1),
            "t" : NumberLong(2)
        },
        "lastCommittedWallTime" : ISODate("2020-11-19T09:36:24.429Z"),
        "readConcernMajorityOpTime" : {
            "ts" : Timestamp(1605778584, 1),
            "t" : NumberLong(2)
        },
        "readConcernMajorityWallTime" : ISODate("2020-11-19T09:36:24.429Z"),
        "appliedOpTime" : {
            "ts" : Timestamp(1605778584, 1),
            "t" : NumberLong(2)
        },
        "durableOpTime" : {
            "ts" : Timestamp(1605778584, 1),
            "t" : NumberLong(2)
        },
        "lastAppliedWallTime" : ISODate("2020-11-19T09:36:24.429Z"),
        "lastDurableWallTime" : ISODate("2020-11-19T09:36:24.429Z")
    },
    "lastStableRecoveryTimestamp" : Timestamp(1605778554, 1),
    "electionCandidateMetrics" : {
        "lastElectionReason" : "electionTimeout",
        "lastElectionDate" : ISODate("2020-11-19T09:17:54.388Z"),
        "electionTerm" : NumberLong(2),
        "lastCommittedOpTimeAtElection" : {
            "ts" : Timestamp(0, 0),
            "t" : NumberLong(-1)
        },
        "lastSeenOpTimeAtElection" : {
            "ts" : Timestamp(1605777471, 8),
            "t" : NumberLong(1)
        },
        "numVotesNeeded" : 1,
        "priorityAtElection" : 5,
        "electionTimeoutMillis" : NumberLong(10000),
        "newTermStartDate" : ISODate("2020-11-19T09:17:54.390Z"),
        "wMajorityWriteAvailabilityDate" : ISODate("2020-11-19T09:17:54.480Z")
    },
    "members" : [
        {
            "_id" : 0,
            "name" : "mongodb-primary:27017",
            "health" : 1,
            "state" : 1,
            "stateStr" : "PRIMARY",
            "uptime" : 1112,
            "optime" : {
                "ts" : Timestamp(1605778584, 1),
                "t" : NumberLong(2)
            },
            "optimeDate" : ISODate("2020-11-19T09:36:24Z"),
            "syncSourceHost" : "",
            "syncSourceId" : -1,
            "infoMessage" : "",
            "electionTime" : Timestamp(1605777474, 1),
            "electionDate" : ISODate("2020-11-19T09:17:54Z"),
            "configVersion" : 61323,
            "configTerm" : -1,
            "self" : true,
            "lastHeartbeatMessage" : ""
        },
        {
            "_id" : 1,
            "name" : "mongodb-arbiter:27017",
            "health" : 1,
            "state" : 7,
            "stateStr" : "ARBITER",
            "uptime" : 1108,
            "lastHeartbeat" : ISODate("2020-11-19T09:36:24.649Z"),
            "lastHeartbeatRecv" : ISODate("2020-11-19T09:36:24.666Z"),
            "pingMs" : NumberLong(0),
            "lastHeartbeatMessage" : "",
            "syncSourceHost" : "",
            "syncSourceId" : -1,
            "infoMessage" : "",
            "configVersion" : 61323,
            "configTerm" : -1
        }
    ],
    "ok" : 1,
    "$clusterTime" : {
        "clusterTime" : Timestamp(1605778584, 1),
        "signature" : {
            "hash" : BinData(0,"WD1gDogfO+q0uWoLOy2tvycsDx8="),
            "keyId" : NumberLong("6896761722598588420")
        }
    },
    "operationTime" : Timestamp(1605778584, 1)
}


Solution

  • Add this parameter to your connection string:

    directConnection=true
    

    Like this:

    mongodb://root:password123@localhost:27017/streamhatchet?directConnection=true&authSource=admin&replicaSet=replicaset&retryWrites=true
    

    References:

    https://www.mongodb.com/docs/drivers/go/current/fundamentals/connection/#connection-options

    https://www.mongodb.com/docs/mongodb-shell/connect/#connect-to-a-replica-set

    https://pkg.go.dev/go.mongodb.org/mongo-driver@v1.9.0/mongo/options#ClientOptions.SetDirect


    Why Did Adding "directConnection=true" Fix the Issue?

    The directConnection=true flag forces the MongoDB client (Mongoose in your case) to connect directly to the specified host, rather than attempting to discover a replica set.
    By default, when you connect to MongoDB, the driver tries to auto-discover a replica set. This is useful if you have a cluster (multiple MongoDB instances), but in your case, you're running a single instance locally.
    By adding directConnection=true, you're telling Mongoose:

    Skip the replica set discovery process. Connect directly to the specified MongoDB node.