dns

DNS is something so fundamental to most of our systems functioning that it’s often overlooked in initial troubleshooting, it’s also incredibly hard to troubleshoot if it’s only intermittently failing.

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When using netplan it is easy to force .local DNS requests to go to you nameservers instead of being only resolved locally (the default and standard).

This also works with all other strange .WHATEVER domains you may have lying around in your organization.

Snippet from netplan configuration:

 nameservers:
        addresses:
          - X
          - Y
        search:
          - local
          - myotherstupiddomain

Usually at least one of those is present on any system

• dig
• nslookup
• host

But sometimes the usual suspects don’t work, especially in container-land. After trying them you may try some more involved/unknown things:

getent

Part of glibc, this will probably work on nearly every system.

getent hosts example.org

Or, if you specifically want to query A or AAAA records.

getent ahostsv4 example.org
getent ahostsv6 example.org

Using Python2 Or Python3

Given this depends on glibc it is more of a alternative then another real solution.

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