Q: My site went down but the server was healthy. Could it be DNS?
A: Very possibly, and most uptime setups never check it. If your domain stops resolving, a fat-fingered record, an expired domain, or a registrar/DNS-provider outage, the server can be perfectly fine while every user gets "site can't be reached."
Add these alongside your HTTP check:
— A DNS check that confirms your A/AAAA records resolve to the IPs you expect (not just "resolves", but resolves to the right address).
— Domain expiry monitoring, because a lapsed renewal is a self-inflicted, totally avoidable outage.
The follow-up worth pre-empting: if you use GeoDNS or a managed DNS provider with multiple nameservers, query each nameserver directly. A single broken nameserver can serve stale or wrong records to a slice of your users while the others look fine, which is murder to debug without per-nameserver visibility.
Got a question? Drop it in the comments.
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Q: My site went down but the server was healthy. Could it be DNS?
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