I am on GMT+8 and I set my hwlock to UTC.
[root@sjoam2 ~]# date
Sat Aug 1 16:32:04 SGT 2015
[root@sjoam2 ~]# hwclock --systohc --utc
[root@sjoam2 ~]# hwclock --debug
hwclock from util-linux-ng 2.17.2
Using /dev interface to clock.
Last drift adjustment done at 1438417931 seconds after 1969
Last calibration done at 1438417931 seconds after 1969
Hardware clock is on UTC time
Assuming hardware clock is kept in UTC time.
Waiting for clock tick...
...got clock tick
Time read from Hardware Clock: 2015/08/01 08:32:17
Hw clock time : 2015/08/01 08:32:17 = 1438417937 seconds since 1969
Sat 01 Aug 2015 04:32:17 PM SGT -0.641290 seconds
[root@sjoam2 ~]#
Seems fine.
hwclock debug is showing 08:32 UTC
— I am not so sure on the last sentence in hwclock –debug
(Sat 01 Aug 2015 04:32:17 PM SGT -0.641290 seconds)
whereby it shows the date in current timezone format (which is +8 hours) – i assume its fine
After reboot
[root@sjoam2 ~]# hwclock --debug
hwclock from util-linux-ng 2.17.2
Using /dev interface to clock.
Last drift adjustment done at 1438417931 seconds after 1969
Last calibration done at 1438417931 seconds after 1969
Hardware clock is on UTC time
Assuming hardware clock is kept in UTC time.
Waiting for clock tick...
...got clock tick
Time read from Hardware Clock: 2015/08/01 08:36:45
Hw clock time : 2015/08/01 08:36:45 = 1438418205 seconds since 1969
Sat 01 Aug 2015 04:36:45 PM SGT -0.782726 seconds
[root@sjoam2 ~]#
Still seems ok from hwclock –debug output
Hwclock = 08:36
— I am not so sure on the last sentence in hwclock –debug (Sat 01 Aug 2015 04:36:45 PM SGT -0.782726 seconds) whereby it shows the date in current timezone format (which is +8 hours) – i assume its fine
But look at date now
[root@sjoam2 ~]# date
Sun Aug 2 00:40:31 SGT 2015
It is adding another 8 hours to the correct time of the hwclock last output
Sat 01 Aug 2015 04:36:45 PM SGT + 8 more hours, which is adding a total of 16 hours to the UTC timing
How do i prevent that ? Where has my configurations gone wrong.
Best Answer
I synchronized
date
andhwclock
with this command:Above command writes
date
time tohwclock
time.NOTE: If you want write
hwclock
time todate
time do it:For test:
NOTE: You can use
hwclock -s
instead ofhwclock --hctosys
andhwclock -w
instead ofhwclock --systohc
.