I volunteer supporting a news website in Russia, which was hand-crafted in PHP back in 2002-2004. Needless to say, I was super excited when editors hired some folks to build a new version, based on WordPress.
The old site is running on mydomain.press. I put the new WordPress version, which is meant to replace the old one, on subdomain.mydomain.press.
And there’s a mysterious problem with it.
When an editor is trying to access the site at subdomain.mydomain.press, her browser (Chrome in Russia) instantly reports err_connection_reset, in 9 cases out of 10. Not spinning trying to load the site – an instant error is reported.
On my machine (Canada) the same website opens no problem. Well, a little slow (hence I mentioned she’s not even seeing the delay – the error is instant), but it opens in 10 out of 10 trials.
When her Chrome gets the content (in that 1/10 case), it also shows a slight delay. Only the error case is instantaneous. The old site at mydomain.press is opening 100% of the time.
Connecting remotely to her Windows machine (I’m using Mac OS X) via TeamViewer, I did observe the behaviour described when using Chrome. Interestingly enough, IE didn’t show this problem – it loads consistently, except that once in ~10 reloads the page loads with a garbled styling. As if some css isn’t loaded properly (but not in a way that would make it an invalid document, obviously).
I’m completely out of my depth. I tried disabling her Windows Defender to see if it’s the culprit – nope. I’ve tried to reset her IP address (as suggested by the same page which offered the earlier way to try and fix the err_connection_reset) – no dice.
I’m not seeing either error from my own Chrome, nor the garbled css (though I didn’t try with IExplorer from Canada).
I know they had some ISPs in Russia block them (silly political reason, AFAIK) in the past – but this doesn’t look like blocking; she’d be 100% unable to view it otherwise. She’s not under any firewall (nor is the website).
what else… nginx is the server used, the setup is “basic”, I suppose (I’m not that proficient in configuring it to try anything fancy).
And to make things even more mysterious – the website at mydomain.press (the old version, php-hand-crafted) is opening just fine, 100% of trials.
Opening using the IP-address doesn’t change the picture, so doesn’t look like a DNS issue.
There is an ongoing battle of Roskomnadzor against Telegram messenger in Russia, which affects subnets, DNS and DPI hardware around the country. Try to connect via proxy or VPN server outside Russia and see if the problem goes away.