Google Public DNS routing to unreachable Cloudflare Anycast IPs for specific domain

Application Performance DNS & Network
1

What is the name of the domain?

What is the issue you’re encountering

We are experiencing a DNS-related issue affecting the availability of two of our websites — rissalat.com and iislb.com — when accessed through devices using Google Public DNS (8.8.8.8). The issue appears to be due to the IPs returned by Cloudflare’s proxy system being unreachable from certain networks or regions. Domains Affected: - rissalat.com - iislb.com Problem Description: When using Google Public DNS (8.8.8.8) as the resolver, these domains resolve to Cloudflare Anycast IP addresses that appear to be inaccessible or timing out from some client networks. The websites do not load and return the browser error: ERR_CONNECTION_TIMED_OUT In contrast, when using Cloudflare DNS (1.1.1.1) or other public resolvers (like Quad9 or OpenDNS), the domains resolve to different Cloudflare IPs and the sites work perfectly. Example: rissalat.com :cross_mark: Google DNS result (problematic): nslookup rissalat.com 8.8.8.8 Addresses: 188.114.96.7 188.114.97.7 :white_check_mark: Cloudflare DNS result (working): nslookup rissalat.com 1.1.1.1 Addresses: 104.21.93.81 172.67.207.154 Example: iislb.com :cross_mark: Google DNS result (problematic): nslookup iislb.com 8.8.8.8 Addresses: 188.114.96.3 188.114.97.3 :white_check_mark: Cloudflare DNS result (working): nslookup iislb.com 1.1.1.1 Addresses: 104.21.93.146 172.67.170.192

What steps have you taken to resolve the issue?

Actions Taken:

  • Verified origin server is working correctly.
  • Disabled firewall and tested without plugins/themes (WordPress).
  • Flushed DNS cache at Flush Cache - Google Public DNS for A records.
  • Compared resolution between Google DNS and Cloudflare DNS.
  • Manually added the working Cloudflare IPs to the hosts file — confirmed websites load correctly.
    This confirms it’s a DNS routing issue specific to the Cloudflare IPs returned by Google DNS.

What feature, service or problem is this related to?

DNS records

2

Cloudflare can return different IP addresses at times, or in different regions. All Cloudflare proxy IPs answer for all sites anyway so getting different IPs shouldn’t be a problem. It’s possible that the 188.114 IPs are being blocked by your ISP. Use a traceroute, or preferably TCP traceroute to port 443, to see where the problem is.

curl -i http://rissalat.com/ --connect-to ::188.114.96.7
HTTP/1.1 301 Moved Permanently
Date: Fri, 04 Jul 2025 08:28:25 GMT
Transfer-Encoding: chunked
Connection: keep-alive
Location: https://rissalat.com/
Report-To: {"group":"cf-nel","max_age":604800,"endpoints":[{"url":"https://a.nel.cloudflare.com/report/v4?s=4ABDk%2FbnAWrCACHF%2BCBdu6tEEn%2Fw52HlZhBdLFCovCSzuBe%2FOAjEfMLspJXMgZshIvYdsh8qkFWuX%2FxjoiTk3rVvKOFFwKlosx%2ByZA%3D%3D"}]}
Nel: {"report_to":"cf-nel","success_fraction":0.0,"max_age":604800}
Server: cloudflare
CF-RAY: 959d3fc4ef63b84d-LHR
alt-svc: h3=":443"; ma=86400
Server-Timing: cfReqDur;dur=10.773