Add graphical method to set the timezone, time and add NTP

[shasheene]

A user named dave duran on Rescuezilla's Sourceforge forum requested the ability to modify the time.

I responded:

Rescuezilla v1.0.6.1 does not yet have an easy-to-use graphical method to modify the time. It's possible to use the command-line to set the time using the date utility, but this will be too difficult for many users. I expect many of those who want to change the time in Rescuezilla may actually really want to change the timezone, as Rescuezilla sets its timezone to UTC+0 (Greenwich Mean Time Zone).

It's worth noting that when Rescuezilla boots it reads the time from the hardware clock built in to a computer's motherboard. This leads to funny situations because on Windows that value is set and read using local time, and on standard Linux environments that hardware clock value is set and read as UTC+0, with the timezone only applied after. This difference causes standard Windows and Linux dualboot environments to not display time correctly without careful configuration. There's no standard solution to this Windows/Linux time display issue, and it's not possible to handle the situation through autodetection. To avoid adding to this situation, Rescuezilla itself does not set the motherboard hardware clock, but it does read and interpret it.

An additional consideration is all changes made to Rescuezilla itself disappear on reboot, because as of writing Rescuezilla does not yet offer a persistent environment. (I will eventually implement a persistent environment as part of task #8).

I will add NTP (Network Time Protocol), so that the time (but not timezone) is automatically retrieved over the internet. Rescuezilla should definitely provide a graphical ability to set the time and timezone, in addition to a graphical method to select a keyboard layout (task #91).

(EDIT: While I note that the NTP utility is not installed, as far as I can tell the internal systemd-timesyncd background service is already providing Network Time Protocol client functionality)

This issue is relatively low priority until the Rescuezilla frontend has become an application worth being widely used.

To anybody reading this: feel free to comment with your input, choose reactions etc.

[zebradots]

Hi @shasheene,

FYI, for the time being Redo has elected to disable the time sync provided by systemd-timesyncd because it appears it can alter the time for Windows users (similar to what happens to those who dual-boot Linux and Windows). Since the timezone doesn't appear to be able to be autodetected (as evidenced by the fact that virtually every OS installer asks for this information), it may be prudent to simply ignore it for the short duration of the backup/restore operation. While it may be a little annoying to see an incorrect time on the taskbar, it's worse to have to re-set the system time after every backup. If there is a way to sync without causing this issue (e.g. set local RTC first), we are hoping to find out how, and will let you know if we do.

[shasheene]

Thanks for raising this. I was aware that Windows machines set the hardware clock in localtime and Linux machines set it in UTC, but didn't realize systemd-timesyncd was modifying the hardware clock rather than just the system clock.

I agree the key is for the NTP update to occur without modifying the hardware clock. I might switch from using systemd-timesyncd to ntpd, with the kernel's "11 minute mode" synchronize disabled via running hwclock -hctosys (which Rescuezilla happens to already run at boot).

There are a lot of subtle considerations when it comes to system time (and NTP), so I will give it some thought.