If I want to change the disposable time zone, where should I modify it? The disposable template? The template of the disposable template? Or dom0?
dom0’s timezone is sent to every qubes when they start up, meaning they all have the same value.
If you want a specific timezone for a qube, you will need to modify it manually. In your case, you need to change it in the disposable template so that the change is inherited by disposable qubes.
/rw/config/rc.local:
timedatectl set-timezone <timezone>
ln -sf /usr/share/zoneinfo/<timezone> /etc/localtime
# If on Q4.3, anon-timezone can be used instead
# qvm-features <qube> anon-timezone 1
qubesdb-rm /qubes-timezone
For a more structured way using vm-config:
# In dom0:
# qvm-features <qube> vm-config.timezone <timezone>
TIMEZONE=$(qubesdb-read /vm-config/timezone)
timedatectl set-timezone $TIMEZONE
ln -sf /usr/share/zoneinfo/$TIMEZONE /etc/localtime
# If on Q4.3, anon-timezone can be used instead
# qvm-features <qube> anon-timezone 1
qubesdb-rm /qubes-timezone
If you want to change it flexible do it in the disposable.
Terminal:
to see time zones: timedatectl list-timezones ( press q to exit list)
to set new time zone: timedatectl set-timezone Region/City.
If you want to to it permanent for the disposable clone the template and change it there.