Connecting the same MongoDB Atlas database to a local app and a railway deployed app

I have developed a web-app using Express (Node.js/JavaScript) web frameworks, initially following a MDN tutorial but flying solo now. There is an MongoDB Atlas database, for the data, connected to the app and working very well. On deploying the app via Railway, without a database service, I expected to be able to connect to the same Atlas database using the same connection script "mongodb+srv://<username>:<password>". This failed to connect even though I had a white-listed IP (

Many hours of reading and experimenting followed including replacing the Atlas DB with a MongoDB service in the Railway container. Long story short over 24 hours after having added a white-list IP to my Atlas account the app on Railway connected to the Atlas database!! Clearly my problem is resolved but I thought it might be a good discussion topic for my first post on this forum. Thanks for “listening”.


Hey, where do you find your Railway outbound IP’s to add to the Atlas database?

Thanks for pointing me into right direction. In my case it was insta-change on atlas part and everything worked. I’m on free tier.

This really saved me a lot of grief. Thank you so much !