Is It Down?

Down for you or down for everyone

A check from an independent network distinguishes a site-wide outage from a local problem. If the site responds elsewhere and not for you, the fault is between your device and the site — DNS cache, ISP routing, a firewall, a VPN, or a block applied to your address. Establishing which side the fault is on takes seconds and saves an hour of the wrong troubleshooting.

What each response means

Connection refused means a host answered and nothing was listening on that port. Timeout means no reply at all, typically a firewall dropping packets silently or a host that is unreachable. DNS failure means the name did not resolve, which is a different outage entirely — often an expired domain or a nameserver problem rather than a server one. A 5xx status means the server is running and the application is failing.

200 does not mean working

A site can return 200 while serving an error page, an empty template or a maintenance notice. Availability checks that only look at the status code miss the most common form of partial outage, which is why real monitoring asserts on page content rather than the code alone.

Regional outages are common

CDN and DNS problems frequently affect some regions and not others, so a single external check can report healthy while a whole continent cannot reach the site. Checking from several locations is the only way to see this.

Rule out the cheap causes first

A stale DNS cache after a record change, a VPN routing traffic through a blocked exit, an expired certificate producing a browser refusal that looks like an outage, or an IP-based rate limit from earlier testing. Each is far more common than an actual site failure and each takes under a minute to eliminate.

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