DNS health checks: connect endpoint health to the record

Cloud DNS health checks monitor endpoints and remove them from eligible GeoDNS and weighted answers when they fail.

Aptranet editorial21 May 20264 min read

Static DNS will keep handing out an address after the application behind it is gone. Health checks make eligibility a measured fact, then a one-second TTL makes that fact usable.

Probe what you publish

Check the addresses you actually return, over the protocol that means up for that service — often HTTPS. Probing IPv4 only while publishing AAAA is how dual-stack surprises start.

Policy honours health

GeoDNS and weighted pools should exclude unhealthy endpoints automatically. A nearby region that is down is not nearby in any useful sense.

Alert anyway

DNS failover is not a substitute for knowing a region is down. Health checks decide answers. APM explains why.

Avoid flaps

Set sensitivity so a single blip does not churn records. Rehearse failure in staging until the DNS graph is boring.

Frequently Asked Questions

What if every endpoint is down?

Plan the empty-set behaviour with Aptranet. Do not assume DNS can invent a healthy target.

Are checks IPv6-capable?

Cloud DNS supports IPv4 and IPv6 records. Probe the addresses you publish.

Do checks replace uptime robots?

They can feed DNS. You still want independent monitoring and paging.

Probe what you publish

Policy honours health

Alert anyway

Avoid flaps

Keep reading

Frequently Asked Questions

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