I've been running several client websites on a dedicated VPS in the UK, all utilizing a CloudFront CDN PAYG distribution configured the same way for quite some time. Recently, I've encountered issues where some users, particularly those outside the UK, are unable to fully load these sites. I've resolved several CORS errors during my checks, and based on my own testing in the UK using Edge, Chrome, and Firefox, everything seems to be working fine. However, some users from the US are still experiencing problems with CORS and 502 errors while others are not facing any issues. I've run tests through BrowserStack, where some states show no problems while others exhibit the same errors that I thought were fixed. The errors I'm seeing include browser console messages indicating blocked images and JavaScript files, often related to CORS policies or bad gateway errors. I'd really appreciate any insights into why this is happening and tips on how to resolve it, especially since I'm losing business opportunities due to these issues. Thanks!
3 Answers
Have you checked for any shared resources across your client sites? Sometimes, caching issues can cause one site's cache to conflict with another, leading to problems. Just double-check that everything is indeed isolated as you believe it is.
Have you reached out to AWS support about this? They can classify it as a production issue and assist with any potential misconfigurations on your end.
We've had similar issues, and often it comes down to the specific browser setup. It's tricky to troubleshoot unless you can replicate the problem consistently. Make sure to gather details on OS, browser versions, and any extensions that users might have. We had a case where doing a HEAD request first cleared a cache miss and allowed the subsequent GET request to work without error.

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