mw/kubernetes: document stubDomain proxy
Mention stubdomains in the documentation, give an example  and fix a few
typos.
Fixes
@@ -8,6 +8,9 @@ CoreDNS running the kubernetes middleware can be used as a replacement of kube-d
cluster. See the [deployment](https://github.com/coredns/deployment) repository for details on [how
to deploy CoreDNS in Kubernetes](https://github.com/coredns/deployment/tree/master/kubernetes).
+[stubDomains](http://blog.kubernetes.io/2017/04/configuring-private-dns-zones-upstream-nameservers-kubernetes.html)
+are implemented via the *proxy* middleware.
+
## Syntax
~~~
@@ -16,7 +19,7 @@ kubernetes [ZONES...]
With only the directive specified, the *kubernetes* middleware will default to the zone specified in
the server's block. It will handle all queries in that zone and connect to Kubernetes in-cluster. It
-will not provide PTR records for services, or A records for pods. If **ZONES** is used is specifies
+will not provide PTR records for services, or A records for pods. If **ZONES** is used it specifies
all the zones the middleware should be authoritative for.
```
@@ -76,25 +79,49 @@ Also handle all `PTR` requests for `10.0.0.0/16` . Verify the existence of pods
requests. Resolve upstream records against `10.102.3.10`. Note we show the entire server block
here:
+~~~ txt
10.0.0.0/16 cluster.local {
kubernetes {
pods verified
upstream 10.102.3.10:53
}
}
+~~~
Or you can selectively expose some namespaces:
+~~~ txt
kubernetes cluster.local {
namespaces test staging
}
+~~~
-And finally we can connect to Kubernetes from outside the cluster:
+Connect to Kubernetes with CoreDNS running outside the cluster:
+~~~ txt
kubernetes cluster.local {
endpoint https://k8s-endpoint:8443
tls cert key cacert
}
+~~~
+
+Here we use the *proxy* middleware to implement stubDomains that forwards `example.org` and
+`example.com` to another nameserver.
+
+~~~ txt
+cluster.local {
+ kubernetes {
+ endpoint https://k8s-endpoint:8443
+ tls cert key cacert
+ }
+}
+example.org {
+ proxy . 8.8.8.8:53
+}
+example.com {
+ proxy . 8.8.8.8:53
+}
+~~~
## AutoPath
