We use Amazon Cloudfront to serve static content. We now find, that users who upgraded to iOS 10, AND who are connected via public wifi (optimumwifi), get a 502 error for any Cloudfront page. The error message is as follows:
Cloudfront attempted to establish a connection with the origin, but either the attempt failed or the origin closed the connection.
This is a false message for 2 reasons, as the origin is reachable, and as the Cloudfront page is reachable from all other device or when using private wifi. In addition, there is no reason that Cloudfront should be attempting to get the origin, as the page should be cached already, and it should be serving the cached version.
I have found a similiar post at iOS > v10.0 devices not playing videos from a CloudFront distribution using signed cookies , but we do not use any cookies, so that shouldn't be the issue.
This issue happens when calling the page from Safari, both http and https. You can test the issue at the following link: http://d1286uoz7ltgna.cloudfront.net/lion.jpg, which will work from most devices, but not on iOS 10 when on optimumwifi. I hope anyone out there has a solution for this wierd issue.