MongoDB Atlas Database
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MongoDB Atlas Database
MongoDB bought mLab in 2018 and shutdown its service in 2020. Most users migrated to MongoDB Atlas, using a free M0 database with a limited 512MB capacity. Leaving the database grow uncontrolled usually leads to a Nightscout crash.
The M0 cluster is free
Nightscout was adapted to MongoDB Atlas
M0 clusters are designed for learning and testing, not production
There is no warranty the M0 cluster will remain in the future
A larger M2 cluster costs 9$ per month (consider hosted Nightscout)
A full M0 database crashes Nightscout, this is a common issue for DIY closed loop system users
MongoDB Atlas regularly changes the site aspect. If you encounter a page not matching this documentation search for keywords like
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Create an Atlas database
a) Open a browser tab at: https://www.mongodb.com/cloud/atlas/register
b) Enter your information, click
MongoDB Atlas will send you an email, if you don’t receive it check your Spam folder.
In the email you received from MongoDB Atlas (mongodb-atlas @ mongodb.com), click on
Another browser tab will open with your confirmed MongoDB account,
Enter some information (like below) and click
Create a cluster in Shared Clusters (FREE)
If you ever see this, just STOP
We’re building a free cluster: you don’t need to provide any billing information.
d) Check you selected
Shared, leave all default values and click
Username and Password and invent a database username (for example
nightscout) and a database password (for example
soo5ecret but please make one that’s yours!).
Do not use your Atlas account credentials. Do not use special characters: only letters and numbers. No spaces.
Write down the password in the line below (yes, in this browser window you’re reading now, unless you’re reading a printed version). You’ll need it later.
Database password (write here ->)
My Local Environment and in the box
My IP address write
0.0.0.0/0 (mind these are all zeroes, not the letter O)
If you don’t allow access from anywhere (IP 0.0.0.0/0) Nightscout will not be able to access your database.”
g) Click on
Finish and Close
h) Click on
Go to Databases
i) Atlas will create your default cluster, it can take more than 3 minutes
j) Click on
k) If displayed, click on
Choose a connection method (else skip)
Connect your application
m) Copy the connection string: click
Copy and paste it somewhere to edit it (like Notepad).
n) Paste the string in the line below (yes, in this browser window you’re reading now, unless you’re reading a printed version).
(paste here ->)
It should be similar to this (
xxxxx will be different):
o) (Optional) Invent a name for your database, this is not a critical information (for example
myCGMitc). Only letters and numbers, no spaces.
Database Name (write here ->)
p) Click on the button
Generate (just here below this line: in this browser window you’re reading):
The connection string will appear here
Keep this string safely aside, it is called your
p) If you want to do it manually: replace
<password> with your database password as noted previously (in the example below
<dbname> by any text you want, say
mycgmic for example. The result will be like this:
There should be NO
< and NO
> characters in the final string, neither for password nor for database name.
You have completed a MongoDB Atlas database creation.
Now that you have copied the resulting
MONGODB_URI string to a safe place, go back to the instructions page you were following.