[networking tools] Add the dnstools image which contains dig utility

Description

dnstools with dig

kubectl run --kubeconfig kubeconfig-headless.yaml -it --rm --restart=Never dns-test --image=infoblox/dnstools:latest

Reasons

dig is a very useful tool to help troubleshoot custom domains against a variety of DNS servers

Attachments

kubectl run --kubeconfig kubeconfig-headless.yaml -it --rm --restart=Never dns-test --image=infoblox/dnstools:latest

dnstools# dig @223.6.6.6 _:<mydomain.com>


; <<>> DiG 9.11.3 <<>> @223.6.6.6 _:<mydomain.com>
; (1 server found)
;; global options: +cmd
;; connection timed out; no servers could be reached
dnstools# 
dnstools# dig @1.1.1.1 _:<mydomain.com>

; <<>> DiG 9.11.3 <<>> @1.1.1.1 _:<mydomain.com>
; (1 server found)
;; global options: +cmd
;; connection timed out; no servers could be reached
dnstools# dig @8.8.8.8 _:<mydomain.com>

; <<>> DiG 9.11.3 <<>> @8.8.8.8 _:<mydomain.com>
; (1 server found)
;; global options: +cmd
;; connection timed out; no servers could be reached
dnstools# dig

; <<>> DiG 9.11.3 <<>>
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 39964
;; flags: qr rd ra; QUERY: 1, ANSWER: 13, AUTHORITY: 0, ADDITIONAL: 27

Start by inspecting the repository for existing container image definitions and the build or publishing entry points; no specific file is named in the issue. Use the provided kubectl run command to check that the new dnstools image starts successfully and that dig is available for DNS troubleshooting.