I'm trying to resume a Node.js project that was working correctly about six months ago. I am now unable to connect to my MongoDB Atlas cluster.

The problem occurs with both the MongoDB SRV connection string and the standard non-SRV connection string, but they produce different errors.

Environment

• Windows 11 / Linux Mint (latest version)

• Node.js v24.20.0

• Mongoose 9.9.5

• MongoDB Node.js driver 7.5.0

• MongoDB Atlas free (M0) cluster

• My current public IP is added to the Atlas IP access list

• The cluster is accessible normally through the Atlas website

The problem occurs on both Windows and Linux.

I am currently using an open/public Wi-Fi network. However, I also tested using a mobile phone hotspot and got the same results.

1. SRV connection

Using the normal Atlas connection string:

mongodb+srv://...

I get:

MongoNetworkError: querySrv ETIMEOUT _mongodb._tcp..mongodb.net

I tested the DNS resolution separately.

For example:

nslookup -type=SRV _mongodb._tcp..mongodb.net 1.1.1.1

times out.

I also tried Google's DNS server:

nslookup -type=SRV _mongodb._tcp..mongodb.net 8.8.8.8

and the SRV lookup also times out.

However, the Atlas hostname itself can be resolved, so this does not appear to be a complete failure to resolve the MongoDB domain.

I also tested the connection using a mobile hotspot instead of the Wi-Fi network, but the same SRV timeout occurs.

2. Non-SRV connection

I then tried using the standard connection string generated by Atlas:

mongodb://...

This contains the individual MongoDB hosts instead of using the SRV record.

This gets past the SRV/DNS lookup, but the connection then fails with:

MongoNetworkError: 0C550000:error:0A000438:SSL routines:ssl3_read_bytes:
tlsv1 alert internal error:
openssl\ssl\record\rec_layer_s3.c:918:
SSL alert number 80

The same TLS error also occurs when connecting with mongosh.

Interestingly, the non-SRV connection did work once, but on the second attempt it started producing the TLS error again without any changes to the project.

What I have already tested

• The connection string has been checked and is correct.

• The Atlas cluster is running and accessible through the Atlas web interface.

• My current public IP is in the Atlas IP access list.

• The issue occurs on both Windows 11 and Linux Mint.

• The issue occurs with both Node.js/Mongoose and mongosh.

• Both SRV and non-SRV connection methods fail, but with different errors.

• I tested both the current open Wi-Fi network and a mobile hotspot, with the same result.

• I have tried both Cloudflare (1.1.1.1) and Google (8.8.8.8) DNS for the SRV lookup.

I'm trying to determine whether this is a network/DNS/TLS issue, an Atlas configuration issue, or something related to the MongoDB driver/OpenSSL versions.

I would appreciate any help or suggestions on what could be causing these errors or how I can troubleshoot and fix the connection.