[Xen] Setting the Guest’s Clock (rdate used)

Setting the Guest’s Clock

Paravirtualized guests may perform their own system clock management, for example, using the NTPD (Network Time Protocol daemon), or the hypervisor may perform system clock management for all guests.

You can set paravirtualized guests to manage their own system clocks by setting the xen.independent_wallclock parameter to 1 in the /etc/sysctl.conf file. For example

“xen.independent_wallclock = 1”

If you want to set the hypervisor to manage paravirtualized guest system clocks, set xen.independent_wallclock to 0. Any attempts to set or modify the time in a guest will fail.

You can temporarily override the setting in the /proc file. For example

“echo 1 > /proc/sys/xen/independent_wallclock”

일반적으로 independent_wallclock 값은 “0” 이며 이것은 Dom0 의 clock을 따라가며

DomU 개별적으로 타임을 설정할수 없다..

하지만 idependent_wallclock 값을 “1” 로 변경하면 DomU 개별적으로 시간설정이 가능하다..