MongoDB vs MongoDB Atlas

Question

I am a new web developer and have some questions regarding MongoDB.

The site I am working on uses references that saved data locally with MongoDB. But after doing some research, I saw something called MongoDB Atlas, which saves data to a cloud. I guess my question is, if I were to host a website would it matter which one I chose to use? Or would I be restricted to Atlas? And why would someone pick one over the other?

Answer 1

MongoDb Atlas is a MongoDb server hosting provided by the same guys who make MongoDb (which means they typically know what they're doing). It's handy to use because everything is automatically configured for you, you get some dashboards, monitoring, backup, upgrades, etc. They have a free layer also (aka M0, it has some important restrictions though, read more at their site). As usual with Cloud offerings, they have good pricing for starters, but these can skyrocket if you're operating at significant scale.

If you choose to install MongoDb server "locally", you would need to configure the cluster yourself (althougth there are plenty of e.g. pre-configured MongoDb docker images out there), configure the backup, arrange monitoring, etc. A lot of work, if you want to do it properly.

Considering above, here is my advice...

Choose MongoDb Atlas when:

1. You have a small personal project
2. You're a startup and you believe that you will have tens of thousands users soon - Altas allows bootstrap things fast and for a relatively small cost
3. You're a medium sized company, you're fine with MongoDb pricing, and you don't expect to grow too much

Choose manual installation of MongoDb when:

1. You have a small single-server project that is not likely to grow into a multi-server deployment. You can run MongoDb docker in the same server - this is usually a bad practice in general, but it works fine for small workloads. I've used this setup (as part of Meteor Up deployment) and it worked fine with thousands of regular users (depends on your application's usage patterns though).
2. You're a Unicorn-level startup or bigger
3. You're building something for internal usage and have restriction of using cloud deployments
4. Your main servers are not located in the cloud. MongoDb cannot batch requests, so it is very important that your MongoDb server is located in the same datacenter as the backend servers, otherwise latency will kill your performance