I’m having trouble getting Cursor Chat to respond—it consistently shows the message:
“Connection failed. If the problem persists, please check your internet connection or VPN.”
I suspect this might be related to a recent change in our company’s firewall settings. Here’s some context:
- I typically access my dev environment via SSH and run Cursor from there. I believe the API requests are being made from that remote machine, not my local host.
- When I tested Cursor Chat locally (on a folder on my host machine), it worked fine—so it seems like the issue is isolated to the SSH environment.
Is there a specific URL, endpoint, or IP address I can target with something like curl to test connectivity to the Cursor API?
For anyone running into similar issues, I reached out to Cursor support via email and got a quick response (not sure if it was a bot or a human, but either way, it was helpful).
The fix that worked for me: disabling HTTP/2 in Cursor’s settings. You can do this by opening the settings (Cmd/Ctrl + ,) and setting "cursor.general.disableHttp2": true. Apparently, this helps in environments where corporate firewalls interfere with HTTP/2 traffic.
The support agent also shared a list of domains you can curl to check connectivity—handy if you need to loop in your IT team:
Interestingly, when I manually ran curl with the --http2 flag, the domains responded just fine—so I’m not entirely sure why disabling HTTP/2 fixed it in-app. I’ve followed up with support to see if they can shed more light on that.