Occassional MongoError connection refused with multiple mongodb connection to differnt url

Working with Data Drivers
1

I’m connecting two database located at different url using similar code as below. The problem is occasionally (not every time), when I deploy the application with docker, I’ll receive MongoError saying connection refused to one of the connection at 27017 port. Not sure if this is a known issue to mongdb nodejs driver?

 const url = 'mongo    db://'
      + `${config.secrets.MONGO_USERNAME}:${config.secrets.MONGO_PASSWORD}@`
      + `${config.fileSvcDb.hostPortUrls}/${config.fileSvcDb.name}`
      + `?${config.fileSvcDb.urlOptions}`;

 const options = {
          useUnifiedTopology: true,
          useNewUrlParser: true,
          connectTimeoutMS: 1000,
          serverSelectionTimeoutMS: 50000,
          poolSize: 3
    };

    MongoClient.connectAsync(url1, options)
    MongoClient.connectAsync(url2, options)