I am creating automated tests for an rsync-like utility and I need to be able to set the clock back 24 hours for one of the tests. However, when I use timedatectl to set the time and date they revert back to the current time after 15 seconds.
Checking timedatectl status I see that it is not running NTP:
# timedatectl status
Local time: Wed 2019-05-15 23:24:17 EDT
Universal time: Thu 2019-05-16 03:24:17 UTC
RTC time: Wed 2019-01-16 02:13:40
Time zone: America/New_York (EDT, -0400)
NTP enabled: no
NTP synchronized: no
RTC in local TZ: no
DST active: yes
Last DST change: DST began at
Sun 2019-03-10 01:59:59 EST
Sun 2019-03-10 03:00:00 EDT
Next DST change: DST ends (the clock jumps one hour backwards) at
Sun 2019-11-03 01:59:59 EDT
Sun 2019-11-03 01:00:00 EST
I also checked and NTPD is not running and nothing is bound to port 123.
Does timedatectl have another method of syncing time? The CentOS 7 test machine is running in a Docker container under a VirtualBox image so Internet connectivity is somewhat limited. I am also testing on CentOS directly on VirtualBox so I will need to solve for the non-Docker case as well.
Best Answer
VBox Guest Additions includes and enables time syncronisation with the host by default.
You can disable this with the following command:
Or add the following line to your yourVM.vbox file