help/content/reference/checkers/dav.en.md

date	author	title	description	weight
2026-06-11T09:00:00+02:00	nemunaire	CalDAV / CardDAV	Discovers and probes a domain's CalDAV and CardDAV servers: well-known/SRV discovery, HTTPS reachability, advertised DAV capabilities, and (with credentials) the authenticated principal, home-set, collections and REPORT flow.	240

The CalDAV and CardDAV checkers verify that a domain's calendar (RFC 4791) and contacts (RFC 6352) servers are discoverable, reachable, and correctly advertise the WebDAV extensions that clients rely on. They are two distinct checkers sharing the same logic: caldav attaches to a CalDAV service (abstract.CalDAV), carddav to a CardDAV service (abstract.CardDAV). The only behavioural difference is the required DAV capability (calendar-access vs addressbook) and a CalDAV-only scheduling check.

Both checkers are service-level: they target the corresponding service published on a subdomain and are configured from that service's own Checks tab. Discovery follows RFC 6764: the checker resolves a context URL from /.well-known/{caldav,carddav} and from _caldavs._tcp / _carddavs._tcp SRV records (with an optional path= TXT hint), then probes that endpoint.

When no credentials are supplied, only the anonymous phase runs (discovery, transport, OPTIONS). Supplying a username and password unlocks the authenticated phase: principal discovery, home-set, collection enumeration and the REPORT probe.

{{% notice style="info" title="TLS posture is out of scope" %}} These checkers confirm only that an HTTPS session can be established to the context URL. Certificate validation (chain, hostname, expiry, ciphers) is deliberately left to the dedicated TLS checker. See {{< relref "/reference/checkers/tls" >}}. {{% /notice %}}

What it checks

Rule	What it verifies	Conditions
dav_discovery	A context URL resolves via /.well-known or SRV.	Critical if no context URL can be resolved. Warning when /.well-known returns 200 instead of a 301/302 redirect (legal but many clients won't follow it). Info when the URL was resolved via SRV but /.well-known is broken.
dav_transport	The HTTPS connection to the context URL is reachable.	Critical if the connection fails.
dav_options	An HTTP OPTIONS request advertises the required DAV capability (calendar-access for CalDAV, addressbook for CardDAV) and the PROPFIND/REPORT methods.	Critical if OPTIONS fails or the capability is missing. Warning if the Allow header lacks PROPFIND or REPORT.
dav_principal	The current-user principal URL is discovered via authenticated PROPFIND.	Critical on failure. Unknown when no credentials are supplied (phase skipped).
dav_home_set	The calendar/addressbook home-set is discovered from the principal.	Critical on failure. Unknown when skipped.
dav_collections	Calendar/addressbook collections enumerate and expose their properties (supported component set, supported address data, display name…).	Critical on failure. Warning if the home-set is empty. Unknown when skipped.
dav_report	The server accepts a minimal calendar-query / addressbook-query REPORT against the first collection.	Critical on failure. Warning if the query returns an unexpected response. Unknown when skipped.
caldav_scheduling	(CalDAV only) When calendar-schedule is advertised, the principal exposes schedule-inbox-URL and schedule-outbox-URL.	Warning if advertised but the URLs are missing or the probe fails. Info when scheduling is not advertised. Unknown when skipped.

The HTML report surfaces the most common misconfigurations as callouts: /.well-known returning 200, no SRV and no well-known (service unreachable), a plaintext SRV record without a secure counterpart, a server not advertising the required DAV class, and the authenticated phase being skipped for lack of credentials.

Options

Both checkers accept the same options.

Option	Meaning	Default
Username	Optional. Supplying credentials unlocks the authenticated checks (principal, home-set, collections, REPORT probe).	(empty)
Password or token	Optional. Paired with the username for HTTP Basic authentication.	(empty)
Explicit context URL	Optional. Bypasses /.well-known and SRV discovery; use for servers with a non-standard layout.	(empty)
Domain name	The domain to probe (auto-filled from the service scope).	(auto)
Timeout (seconds)	Per-request HTTP timeout.	10

In happyDomain

Enable the CalDAV or CardDAV checker from the Checks tab of a CalDAV or CardDAV service. The domain name is filled in automatically; add credentials only if you want the authenticated collection and REPORT checks to run. See {{< relref "/pages/checks" >}} for the full workflow, and {{< relref "/reference/checkers/tls" >}} for the certificate posture of the same endpoints.