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System selecting wrong time due to not UTC

bgstack15

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The problem

I use kickstart files to configure my CentOS 7 virtual machines. One problem I discovered is that the vms can get the wrong time from the hwclock. I guess I haven't mastered ntpd or chronyd. I can always just run ntpdate dns1.ipa.example.com but haven't bothered to set up a cronjob/systemd unit for that. Anyway, I finally discovered how to get the hwclock and system date to actually grab the time correctly from the host OS. If I don't set the timezone correctly in the kickstart file with the --utc option:

timezone America/New_York --utc

I can go modify /etc/adjtime myself. An incorrect file:

0.000000 1499048878 0.000000
1499048878
LOCAL

The correct file replaces the LOCAL with UTC, to tell the system that the hardware clock (hwclock) is showing the UTC time:

0.000000 1499048878 0.000000
1499048878
UTC

A reboot later, and now my vm has the correct time, so I have achieved my ultimate goal of gssapi auth.

References

Weblinks

  1. That such a file exists as /etc/adjtime https://eloquence.marxmeier.com/sdb/html/954237377.html
  2. https://bugzilla.redhat.com/show_bug.cgi?id=672194

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