On those live CDs there should be no NTP daemon running anyway. And even if so we switched which defaults to non-utc for the following reason: rtconutc chronyd assumes by default that the RTC keeps local time (including any daylight saving changes). This is convenient on PCs running Linux which are dual-booted with Windows.
If you keep the RTC on local time and your computer is off when daylight saving (summer time) starts or ends, the computer’s system time will be one hour in error when you next boot and start chronyd. An alternative is for the RTC to keep Universal Coordinated Time (UTC). This does not suffer from the 1 hour problem when daylight saving starts or ends. If the rtconutc directive appears, it means the RTC is required to keep UTC. The directive takes no arguments. It is equivalent to specifying the -u switch to the Linux hwclock program. Note that this setting is overridden when the hwclockfile directive is specified. If one wants to change that he can set rtconutc in /etc/chrony/chrony.conf. But as I said this should only apply once you install it, which by default I thought is not the case. Instead you likely just have systemd-timesyncd running. Which I think defaults to systemctl status hwclock ● hwclock.service Loaded: masked (/dev/null; bad) Active: inactive (dead) And Local time: Di 2018-05-29 09:43:08 CEST Universal time: Di 2018-05-29 07:43:08 UTC RTC time: Di 2018-05-29 07:43:08 Time zone: Europe/Berlin (CEST, +0200) System clock synchronized: yes systemd-timesyncd.service active: yes RTC in local TZ: no So as I read it this already does UTC, here from the man page: set-local-rtc [BOOL] Takes a boolean argument. If "0", the system is configured to maintain the RTC in universal time. If "1", it will maintain the RTC in local time instead. Note that maintaining the RTC in the local timezone is not fully supported and will create various problems with time zone changes and daylight saving adjustments. If at all possible, keep the RTC in UTC mode. Note that invoking this will also synchronize the RTC from the system clock, unless --adjust-system-clock is passed (see above). This command will change the 3rd line of /etc/adjtime, as documented in hwclock(8). I'll re-target this bug at systemd (for systemd-timesyncd) but set it to incomplete until we find out which part of the service exactly sets non-UTC time as I'd think this would be the default. You might start by looking at timedatectl on the live system. ** Also affects: systemd (Ubuntu) Importance: Undecided Status: New ** Changed in: ntp (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1703479 Title: Ubuntu 17.04 & Kubuntu 17.04 LiveCD writes to bios/hardware clock; thereby messing up my installed Windows 10 Pro laptop time To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ntp/+bug/1703479/+subscriptions -- desktop-bugs mailing list email@example.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs