Lab 9.3 - Working with CoreDNS - Discussion

Hi @deepakgcp,

You can also examine the error returned by the kubectl CLI. In this case it is very specific, thus helpful, that the "ubuntu" Pod is not found. Since you have access to the YAML manifest of the Pod, it is easy to examine it and extract the name of the Pod that needs to be replaced it in the exec command. You can also use get command to list objects such as Pods by name, or describe to further display objects' details, such as container names whenever needed.

Regards,
-Chris

I'll note there's other typos in this particular lab, for example the coredns pod does not create a PTR record based on the documentation provided for Lab 9.3, please see the following:

root@nettool:/# dig -x nginx.test.io
 
; <<>> DiG 9.16.1-Ubuntu <<>> -x nginx.test.io
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 15933
;; flags: qr rd ra ad; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1
 
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;io.test.nginx.in-addr.arpa.    IN  PTR
 
;; AUTHORITY SECTION:
in-addr.arpa.       30  IN  SOA b.in-addr-servers.arpa. nstld.iana.org. 2020122003 1800 900 604800 3600
 
;; Query time: 24 msec
;; SERVER: 10.96.0.10#53(10.96.0.10)
;; WHEN: Thu Jan 21 09:16:44 CST 2021
;; MSG SIZE  rcvd: 139
 
root@nettool:/# dig nginx.test.io
 
; <<>> DiG 9.16.1-Ubuntu <<>> nginx.test.io
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 151
;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; WARNING: recursion requested but not available
 
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
; COOKIE: 6770800cf9fcd86f (echoed)
;; QUESTION SECTION:
;nginx.test.io.         IN  A
 
;; ANSWER SECTION:
nginx.default.svc.cluster.local. 30 IN  A   10.100.110.209
 
;; Query time: 0 msec
;; SERVER: 10.96.0.10#53(10.96.0.10)
;; WHEN: Thu Jan 21 09:16:58 CST 2021
;; MSG SIZE  rcvd: 101

$ k get cm -n kube-system coredns -o yaml
apiVersion: v1
data:
  Corefile: |
    .:53 {
        rewrite name regex (.*)\.test\.io {1}.default.svc.cluster.local
        errors
...

Hi,

I just ran into this same issue (pod named "nettool", but "ubuntu" name is still used in the PDF command).
Has the new version you mentioned be released?