Pierre-Olivier Mercier
5ccdd8892f
Add individual reference pages for all domain health checkers (EN/FR), update the homepage feature descriptions in both languages to highlight monitoring, notifications, and domain availability checks.
2.5 KiB
| date | author | title | description | weight |
|---|---|---|---|---|
| 2026-06-11T09:00:00+02:00 | nemunaire | External-reference expiry | Retrieves the WHOIS/RDAP registration facts for the external domains your zone points to, so their expiry can be evaluated. | 50 |
The External-reference expiry checker looks up the registration facts of the external domains your zone refers to. When a record points at a name you do not own (a CNAME to a third-party service, an MX to an external provider, an NS delegation…), the safety of your zone depends on that external domain staying registered. If it expires and is re-registered by someone else, the pointer can be hijacked.
This is a zone-level checker: it enumerates the external targets discovered in the zone and performs one WHOIS/RDAP lookup per distinct registrable domain. Targets sharing the same registrable domain reuse a single lookup, and lookups run with a bounded concurrency so a large zone does not overwhelm the registry.
What it checks
This checker is primarily a collector. It gathers per-target WHOIS facts (registrable name, expiry date, creation date, registrar, status) and publishes them for the dangling-reference checker, which is where the actionable verdicts about expiration, redemption or recent re-registration are emitted.
Its own rule, external_whois_collected, reports only how the collection went:
| Status | Condition |
|---|---|
| OK | WHOIS was collected for every external target |
| Info | Some lookups succeeded and some failed (a partial result), or no external target was reported at all |
| Warning | The WHOIS lookup failed for all external targets |
| Error | The external WHOIS observation could not be read |
{{% notice style="info" title="Verdicts live in the dangling-reference checker" %}} This checker does not decide whether an external domain is dangerously close to expiry. It only retrieves the facts. The expiry, redemption and re-registration verdicts are surfaced by the companion dangling-reference checker, which consumes the facts collected here. {{% /notice %}}
Options
This checker has no user-tunable options. The list of external targets is supplied automatically from the zone's discovered references.
In happyDomain
Enable this checker from the zone's Checks view; see {{< relref "/pages/checks" >}} for how to configure and schedule checks. The discovery of external targets is automatic.
For the registration of the domains you own directly, see {{< relref "/reference/checkers/domain-expiry" >}}.