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CoreDNS Does not Answer with Headless Service in Kubernetes (Doc ID 2538443.1)

Last updated on MAY 07, 2021

Applies to:

Oracle Cloud Infrastructure - Version N/A and later
Linux x86-64

Symptoms

 DNS for the headless service return no answers:

$ kubectl get svc -n kube-system |grep dns
kube-dns ClusterIP 10.96.0.10 <none> 53/UDP,53/TCP 9d
$ dig myapp-svc.default.svc.cluster.local @10.96.0.10
; <<>> DiG 9.9.4-RedHat-9.9.4-73.el7_6 <<>> myapp-svc.default.svc.cluster.local @10.96.0.10
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 43519
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;myapp-svc.default.svc.cluster.local. IN A
;; AUTHORITY SECTION:
cluster.local. 7 IN SOA ns.dns.cluster.local. primary.cluster.local. 1556965940 7200 1800 86400 30
;; Query time: 0 msec
;; SERVER: 10.96.0.10#53(10.96.0.10)
;; WHEN: Sat May 04 11:04:13 GMT 2019
;; MSG SIZE rcvd: 157

Cause

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In this Document
Symptoms
Cause
Solution

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