Hi Team,

Our AKS cluster throwing an intermittent DNS issue(DNS resolution failed)

20210915T201241.606Z [0x80e00783][network][error] dns(Main-Name-Service): tid(1311): Cannot resolve host name 'xxxx.fsis.usda.gov' after 17046 ms..

When I checked the coreDNS logs, I found the below errors.

[ERROR] plugin/errors: 2 xxxx.fsis.usda.gov. A: read udp 10.201.x.20:43262->10.201.x.148:53: i/o timeout
[ERROR] plugin/errors: 2 xxxx.fsis.usda.gov. A: read udp 10.201.x.20:53789->10.201.x.148:53: i/o timeout
[WARNING] No files matching import glob pattern: custom/.override
[WARNING] No files matching import glob pattern: custom/.server

We are struggling understand why this is happening intermittently and fixed automatically after a few mins.

Could anyone please help in fixing the issue.

Hi @SRIJIT-BOSE-MSFT

nslookup from nodes and test tcp-connection from gw pods are working fine.

We are getting this error intermittently but not all the times.

Please let me know if you want to check any other details

Thanks
Sitaram

@Erothu, Sita , thank you for your response.

Based on the intermittent nature of the errors, I believe the best course of action would be to open a Microsoft technical Support Request, since this will require more traces and logs for our engineers to troubleshoot further and identify/eliminate the cause or recommend a fix/workaround.

Also, once you get the issue fixed, request you to reply back here on the thread with the resolution steps for the benefit of the community.