Ingress source

The ingress source creates DNS entries based on Ingress.networking.k8s.io resources.

Filtering the Ingresses considered

The --ingress-class flag filters Ingress resources by a set of ingress classes.
The flag may be specified multiple times in order to
allow multiple ingress classes.

This source supports the --label-filter flag, which filters Ingress resources
by a set of labels.

Domain names

The domain names of the DNS entries created from an Ingress are sourced from the following places:

1. Iterates over the Ingress’s spec.rules, adding any non-empty host.

This behavior is suppressed if the --ignore-ingress-rules-spec flag was specified
or the Ingress had an
external-dns.alpha.kubernetes.io/ingress-hostname-source: annotation-only annotation.

2. Iterates over the Ingress’s spec.tls, adding each member of hosts.

This behavior is suppressed if the --ignore-ingress-tls-spec flag was specified
or the Ingress had an
external-dns.alpha.kubernetes.io/ingress-hostname-source: annotation-only annotation,

3. Adds the hostnames from any external-dns.alpha.kubernetes.io/hostname annotation.

This behavior is suppressed if the --ignore-hostname-annotation flag was specified
or the Ingress had an
external-dns.alpha.kubernetes.io/ingress-hostname-source: defined-hosts-only annotation.

4. If no DNS entries were produced for an Ingress by the previous steps
   or the --combine-fqdn-annotation flag was specified, then adds hostnames
   generated from any--fqdn-template flag.

Targets

The targets of the DNS entries created from an Ingress are sourced from the following places:

1. If the Ingress has an external-dns.alpha.kubernetes.io/target annotation, uses
   the values from that.

2. Otherwise, iterates over the Ingress’s status.loadBalancer.ingress,
   adding each non-empty ip and hostname.