46 lines
1.3 KiB
Markdown
46 lines
1.3 KiB
Markdown
# CoreDNS
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- https://kubernetes.io/docs/concepts/services-networking/dns-pod-service/
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- https://github.com/kubernetes/dns/blob/master/docs/specification.md
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- https://coredns.io/
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CoreDNS has the `kubernetes` plugin, so it returns all k8s service endpoints in well-known format.
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All services and pods are registered in CoreDNS.
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- <service-name>.<namespace>.svc.cluster.local
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- <service-name>.<namespace>
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- <service-name> (if in the same namespace)
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- <pod-ipv4-address>.<namespace>.pod.cluster.local
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- <pod-ipv4-address>.<service-name>.<namespace>.svc.cluster.local
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Any query for a resource in the `internal.$DOMAIN` domain will be given the IP of the Traefik proxy. We expose the CoreDNS server in the LAN via MetalLB just for this capability.
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## Default CoreDNS Configuration
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This is the default CoreDNS configuration, for reference:
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```txt
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.:53 {
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errors
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health { lameduck 5s }
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ready
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log . { class error }
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prometheus :9153
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kubernetes cluster.local in-addr.arpa ip6.arpa {
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pods insecure
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fallthrough in-addr.arpa ip6.arpa
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ttl 30
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}
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forward . /etc/resolv.conf { max_concurrent 1000 }
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cache 30 {
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disable success cluster.local
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disable denial cluster.local
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}
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loop
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reload
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loadbalance
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}
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```
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