Two custom .ru domains hang while netlify.app subdomains work correctly

Support
1

Hello Netlify Support,

I am experiencing the same type of custom-domain routing issue on two separate Netlify projects.

Both projects work correctly and load quickly through their default netlify.app subdomains, but their custom .ru domains fail to load normally in browsers.

Project 1

Working: https://sergey-gordyshev.netlify.app/
Failing custom domain: https://sergey-gordyshev.ru/
Also affected: https://www.sergey-gordyshev.ru/

Project 2

Working: https://afdpro.netlify.app/
Failing custom domain: https://afdpro.ru/
Also affected: https://www.afdpro.ru/

Both custom domains currently show Netlify DNS as active in the Netlify dashboard.

For sergey-gordyshev.ru:

  • Primary domain status is correct
  • Netlify DNS is active
  • HTTPS is enabled
  • Let’s Encrypt certificate has been successfully issued
  • Firewall Traffic Rules: no active rules
  • Rate Limiting: no active rules
  • WAF: disabled

DNS resolution also works correctly.

The important diagnostic result is that the request reaches Netlify and returns HTTP 200, but the response body stalls before the complete HTML is transferred.

Test:

curl.exe --http1.1 -L -o NUL -w "HTTP=%{http_code} SIZE=%{size_download} TIME=%{time_total}\n" --max-time 20 https://sergey-gordyshev.ru

Result:

curl: (28) Operation timed out after 20001 milliseconds with 15641 out of 25856 bytes received

HTTP=200 SIZE=15641 TIME=20.002461

The exact same deployment through the Netlify subdomain downloads completely:

https://sergey-gordyshev.netlify.app/

Result:

HTTP=200 SIZE=26392 TIME=1.284298

The www custom domain behaves the same way after redirecting to the primary domain:

https://www.sergey-gordyshev.ru

Result:

curl: (28) Operation timed out after approximately 20 seconds with 14332 out of 25856 bytes received

HTTP=200 SIZE=14332 TIME=20.178438

Previous HEAD requests returned:

Server: Netlify

so the requests are reaching the Netlify edge.

The issue is not limited to one Windows PC or one browser. I reproduced it on different browsers and also on a mobile phone.

Both netlify.app URLs continue to work normally.

I also noticed another very recent forum report describing almost the same behavior: a custom domain using Netlify DNS hangs/resets while its netlify.app subdomain works correctly.

Could you please investigate custom-domain routing/activation and Netlify Edge/CDN response delivery for these two projects?

In particular, why does the custom domain successfully establish HTTPS and return HTTP 200, but then stall while transferring the response body?

I can provide project IDs, deploy IDs, Netlify request IDs, HAR files, screenshots, DNS diagnostics, or any other information required.

Thank you,
Sergey Gordyshev