Properly parse hostname from metadata#19
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jepio merged 2 commits intoflatcar:flatcar-masterfrom May 11, 2023
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This change splits the hostname supplied by the metadata service using dot as a delimiter instead of a single space. We also validate that the resulting hostname is no longer than 63 characters long. Signed-off-by: Gabriel Adrian Samfira <gsamfira@cloudbasesolutions.com>
jepio
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May 10, 2023
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May 10, 2023
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Hmm. The test case expects that we may have more than one hostname set, delimited by an empty space. Is this documented anywhere? From what I could find, there should be only one hostname returned. When multiple NICs are attached, the hostname on @jepio Should I split by space and then by dot, or would you prefer I change the test? |
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I think it's fine to fix the test case. |
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Added a log message and a new test to validate that truncating the hostname works. |
Signed-off-by: Gabriel Adrian Samfira <gsamfira@cloudbasesolutions.com>
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Properly parse hostname from metadata
This change splits the hostname supplied by the metadata service using dot as a delimiter instead of a single space. This API should return a single FQDN on most clouds.
Sample output from fetching the hostname from the AWS metadata service can be seen here:
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/instancedata-data-retrieval.html
OpenStack has the same kind of output.
We also make sure that the resulting hostname is no longer than 63 characters long.
This will ensure that
/etc/hostnamewill contain a proper short form hostname instead of a FQDN.How to use
Build and then run:
on any VM spun up on a cloud with an ec2 compatible metadata service.
Testing done
Build a flatcar image using this commit and spun up a k8s cluster using kops. Hostname was properly set to the short form, not the FQDN.
Addresses the following issue: kubernetes/kops#15385
changelog/directory (user-facing change, bug fix, security fix, update)/bootand/usrsize, packages, list files for any missing binaries, kernel modules, config files, kernel modules, etc.