"MongoError: no valid replicaset members found" error raised after migration from mLab deployment to MongoDB Atlas deployment

[grassland-curing-cfa]

Issue Description

Due to mLab acquisition by MongoDB, all mLab deployments are required to be migrated onto MongoDB Atlas. I have a Sandbox deployment in mongod version: 3.6.12 (MMAPv1). After I migrated it to a M0 Cluster on Atlas. My Parse-server (version 2.2.5) application deployed on Heroku cannot be started up due to: "MongoError: no valid replicaset members found".

Steps to reproduce

1. Create a free M0 Cluster and MongoDB 4.0 database on MongoDB Atlas, and obtain the connection string,
2. Deploy a Parse-server version 2.2.5 onto Heroku,
3. Set the connection string as config variable on Heroku.
4. Create a HelloWorld Cloud function and print out "Hello World"
5. Connect to Parse-server using cURL and trigger the HelloWorld Cloud function.

Expected Results

"Hello World" is printed

Actual Outcome

The back-end Heroku logs the following msg:

Nov 14 16:20:09 nemp-wa-dev app/web.1: error: Error generating response. { MongoError: no valid replicaset members found
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timeout._onTimeout (/app/node_modules/mongodb-core/lib/topologies/replset.js:660:33)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at ontimeout (timers.js:386:14)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at tryOnTimeout (timers.js:250:5)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timer.listOnTimeout (timers.js:214:5)
Nov 14 16:20:09 nemp-wa-dev app/web.1: name: 'MongoError',
Nov 14 16:20:09 nemp-wa-dev app/web.1: message: 'no valid replicaset members found' } name=MongoError, message=no valid replicaset members found
Nov 14 16:20:09 nemp-wa-dev app/web.1: error: Uncaught internal server error. { MongoError: no valid replicaset members found
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timeout._onTimeout (/app/node_modules/mongodb-core/lib/topologies/replset.js:660:33)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at ontimeout (timers.js:386:14)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at tryOnTimeout (timers.js:250:5)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timer.listOnTimeout (timers.js:214:5)
Nov 14 16:20:09 nemp-wa-dev app/web.1: name: 'MongoError',
Nov 14 16:20:09 nemp-wa-dev app/web.1: message: 'no valid replicaset members found' } MongoError: no valid replicaset members found
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timeout._onTimeout (/app/node_modules/mongodb-core/lib/topologies/replset.js:660:33)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at ontimeout (timers.js:386:14)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at tryOnTimeout (timers.js:250:5)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timer.listOnTimeout (timers.js:214:5)
Nov 14 16:20:09 nemp-wa-dev app/web.1: MongoError: no valid replicaset members found
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timeout._onTimeout (/app/node_modules/mongodb-core/lib/topologies/replset.js:660:33)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at ontimeout (timers.js:386:14)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at tryOnTimeout (timers.js:250:5)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timer.listOnTimeout (timers.js:214:5)

Environment Setup

• Server

  • parse-server version (Be specific! Don't say 'latest'.) : 2.2.25
  • Operating System: Linux on Heroku
  • Hardware: n/a
  • Localhost or remote server? (AWS, Heroku, Azure, Digital Ocean, etc): Heroku

• Database

  • MongoDB version: mongod version: 3.6.12 (MMAPv1)
  • Storage engine: Sandbox
  • Hardware: n/a
  • Localhost or remote server? (AWS, mLab, ObjectRocket, Digital Ocean, etc): mLab

Logs/Trace

Nov 14 16:20:09 nemp-wa-dev app/web.1: error: Error generating response. { MongoError: no valid replicaset members found
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timeout._onTimeout (/app/node_modules/mongodb-core/lib/topologies/replset.js:660:33)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at ontimeout (timers.js:386:14)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at tryOnTimeout (timers.js:250:5)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timer.listOnTimeout (timers.js:214:5)
Nov 14 16:20:09 nemp-wa-dev app/web.1: name: 'MongoError',
Nov 14 16:20:09 nemp-wa-dev app/web.1: message: 'no valid replicaset members found' } name=MongoError, message=no valid replicaset members found
Nov 14 16:20:09 nemp-wa-dev app/web.1: error: Uncaught internal server error. { MongoError: no valid replicaset members found
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timeout._onTimeout (/app/node_modules/mongodb-core/lib/topologies/replset.js:660:33)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at ontimeout (timers.js:386:14)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at tryOnTimeout (timers.js:250:5)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timer.listOnTimeout (timers.js:214:5)
Nov 14 16:20:09 nemp-wa-dev app/web.1: name: 'MongoError',
Nov 14 16:20:09 nemp-wa-dev app/web.1: message: 'no valid replicaset members found' } MongoError: no valid replicaset members found
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timeout._onTimeout (/app/node_modules/mongodb-core/lib/topologies/replset.js:660:33)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at ontimeout (timers.js:386:14)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at tryOnTimeout (timers.js:250:5)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timer.listOnTimeout (timers.js:214:5)
Nov 14 16:20:09 nemp-wa-dev app/web.1: MongoError: no valid replicaset members found
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timeout._onTimeout (/app/node_modules/mongodb-core/lib/topologies/replset.js:660:33)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at ontimeout (timers.js:386:14)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at tryOnTimeout (timers.js:250:5)
Nov 14 16:20:09 nemp-wa-dev app/web.1: at Timer.listOnTimeout (timers.js:214:5)

[dplewis]

Can you update to the latest version of parse server? The MongoDB driver probably addressed this issue.

[grassland-curing-cfa]

Thanks for the prompt answer.
The M0, M2 and M5 Cluster on Atlas only supports MongoDB 4.0.
I am hesitant to update Parse-server to the latest version as my Heroku application is about three year old. Have you had any idea what is the lowest version of Parse-server that supports MongoDB 4.0?

[dplewis]

It’s when 3.1.0 of the mongo driver was added

#4855

Looking at the date you could get away with 2.8.4.

We highly recommend updating to the latest version.

[grassland-curing-cfa]

Thanks so much. I upgraded to 2.8.4 and MongoDB 4.0 started to work.