diff --git a/cluster/addons/dns/README.md b/cluster/addons/dns/README.md index 9b552733727..9bd47d0419b 100644 --- a/cluster/addons/dns/README.md +++ b/cluster/addons/dns/README.md @@ -29,6 +29,20 @@ Services, this resolves to the set of IPs of the pods selected by the Service. Clients are expected to consume the set or else use standard round-robin selection from the set. +### SRV records +SRV Records are created for named ports that are part of normal or Headless +Services. +For each named port, the SRV record would have the form +`_my-port-name._my-port-protocol.my-svc.my-namespace.svc.cluster.local`. +For a regular service, this resolves to the port number and the CNAME: +`my-svc.my-namespace.svc.cluster.local`. +For a headless service, this resolves to multiple answers, one for each pod +that is backing the service, and contains the port number and a CNAME of the pod +with the format `auto-generated-name.my-svc.my-namespace.svc.cluster.local` +SRV records always contain the 'svc' segment in them and are not supported for +old-style CNAMEs where the 'svc' segment was omitted. + + ### Backwards compatibility Previous versions of kube-dns made names of the for `my-svc.my-namespace.cluster.local` (the 'svc' level was added later). For