DNS failover
DNS should stop handing out dead endpoints.
If the origin or region fails and DNS still returns it, every client retries the outage. Failover that waits on a 300-second TTL is not failover.
Health checks monitor endpoints continuously. Unhealthy targets are removed from eligible answers. A one-second minimum TTL lets planned or automatic changes take effect quickly.
Why teams use Aptranet
What DNS failover looks like on this network.
Cloud DNS answers on 210+ Anycast servers, with GeoDNS, health checks and a one-second minimum TTL for change.
Health-aware records
Non-responsive infrastructure is taken out of the answer set.
One-second minimum TTL
Resolvers can pick up a new answer without waiting on a long cache.
DDoS-protected authority
Failover still works if the DNS layer itself is under volumetric attack.
How to set it up
A cutover you can validate before DNS moves.
Create the Cloud DNS configuration, prove it on an Aptranet hostname, then point production DNS when the path looks correct.
- 1List the endpoints that can take traffic
Primary and standby application or origin addresses.
- 2Attach health checks
Monitor each endpoint and exclude it when the check fails.
- 3Set a TTL that matches the RTO
Use a low TTL on records that must move quickly.
- 4Rehearse a failover
Fail a check in staging and confirm resolvers stop receiving that answer.
Outcomes
What changes once the hostname is on Aptranet.
- Dead endpoints can disappear from DNS
- TTLs can be as low as one second
- Standby capacity is only used when needed
- The DNS layer remains reachable under attack
Keep reading
Related pages
More DNS use cases on the same Cloud DNS footprint.
Frequently Asked Questions
No. DNS failover changes the record resolvers receive. BGP failover changes how an address is announced. Many architectures use both.
Some resolvers clamp TTLs. Design for that, and use health-aware answers so even a clamped cache is less likely to point at a dead target.
Yes. Combine health checks with GeoDNS or weighted records so a region can be taken out of the eligible set.
CDN origin groups protect delivery. Cloud DNS failover protects the hostname that clients resolve before they reach a CDN or origin.