One oplog, multiple databases

Setup:

  • 1 Meteor account
  • x Meteor apps
  • 1 MongoDB Atlas Cluster
  • x databases in 1 cluster

Is it secure to configure 1 oplog for multiple Meteor apps, where each app have separate database in MongoDB Atlas in 1 Cluster, therefore they would have to share the ‘/local’ database for oplog?

I want to have x apps with x databases, but in 1 project and in 1 Cluster inside MongoDB Atlas.
Database accounts for reading and writing will be allowed for each Meteor app separately for each database, but since I can’t have multiple oplogs in there I don’t know if it could happen that for example app x could see data from app y.

The credentials itself for databases are not a problem, I am the only one taking care of the server (so nobody else can’t fetch the data via oplog from another app).
The question is if it can happen that on the frontend the apps would see each other data somehow.

And another question is - if the oplog can be like this (many apps writing to 1 ‘/local’ database) - would the performance suffer a lot?
If yes, wouldn’t it be then better to just disable oplog and don’t use it - which part of the app would then suffer the most regarding performance? It would be slowly loading, live refresh would take a lot of time or the server would have higher loads…?

Thanks for any advice or just pointing in a good direction,
Martin

Hi @martin37. Just found this old topic of yours without any replies.
Currently looking into this with exactly the same questions/challenges.
What were the outcomes of your research on the above questions?

Likewise, just found this post. Would also love a answer or update