Connection guide
DNS not resolving?
DNS is the lookup that turns names like onlinecheck.net into addresses your browser can actually reach. When DNS is broken or filtered, the internet starts to look random: some apps work, some sites fail, refreshing changes nothing.
Common DNS symptoms
Typical signs: "server IP address could not be found", pages that load on cellular but die on Wi-Fi, or one browser working while another fails on the same machine because they use different secure-DNS settings.
Use reachability as a clue
A browser cannot see your whole resolver path, but mixed results across Google DNS, Cloudflare, GitHub, and the CDN target are a strong hint that one isolated page being down is not the real story.
What to try
Turn off the VPN for a minute. Check the secure-DNS setting in the browser. Restart the router. Try another network. If nothing helps, send the report to the ISP or IT team. That is what the share summary is for.
Why DNS can look random
Some apps cache addresses for ages. Some browsers do their own secure DNS. Some networks intercept DNS requests at the door. The result is one site working fine while another quietly fails. The reachability grid is the fastest way to see whether the failure is one address or the whole resolver.
What a support team needs
Send the time of the check, browser signal, reachability results, latency, jitter, and the network name if you have it handy. Public IP and ASN help an ISP trace your route, but only attach them if you are comfortable sharing that detail.