System time trouble

[elferozlobo]

I have Fedora 15 desktop with gnome O. S. a year ago, but recently I realize that the system clock doesn't work fine: every system boot it adds 5 hours to the right local time, so I have to type: "#hwclock --hctosys" in order it shows the right time. Time zone clock and bios clock are always ok, but how can I tell Fedora to show the exact local time?.......Thanks

[Gareth Jones]

Is your time-zone set correctly (click on the GNOME clock, then "Date and Time Settings")? Also in the same window, is "Network Time" enabled?

Is your BIOS clock set to local time or to UTC? Linux generally uses UTC internally, and expects the hardware clock to be in UTC unless told otherwise. Local-time BIOS clock is supported too for compatibility with Windows in dual boot situations though. Run system-config-date for a more detailed configuration window which includes the BIOS clock option (last option in the second tab). Use UTC if Linux is the only OS installed, otherwise local-time.

[elferozlobo]

Gnome desktop shows the real system time that it's set, but when I open "Date and Time Settings" box it shows the UTC time (system time+5). If I adjust that clock to local time, system time goes down 5 hours. "Network Time" is disable.

[stevea]

Originally Posted by elferozlobo

I have Fedora 15 desktop with gnome O. S. a year ago, but recently I realize that the system clock doesn't work fine: every system boot it adds 5 hours to the right local time, so I have to type: "#hwclock --hctosys" in order it shows the right time. Time zone clock and bios clock are always ok, but how can I tell Fedora to show the exact local time?.......Thanks

Using the command you've shown ... "hwclock --hctosys" is NOT the correct solution.

Post the output of these ...
cat /etc/adjtime /etc/sysconfig/clock

Briefly ...
The Linux SYSTEM time (software clock) in the OS should always be UTC. ALWAYS.
For Linux it is preferred that the hwclock is also UTC, but Windoze also understands local time on the HWclock, so long as /etc/adjtime reflects the setting.

We can adjust the software clock from the files above. The USERSPACE notion of time is based on the OS/software clock and the /etc/localtime file(binary, should match /etc/sysconfig/clock.

Originally Posted by elferozlobo

Gnome desktop shows the real system time that it's set

"real system time" is a meaningless term. There are four possibly different times involved. The hwclock, the softwareclock, the userspace clock and the wall-clock time. All can be different. I have NO IDEA what you mean by "real system time".

, but when I open "Date and Time Settings" box it shows the UTC time (system time+5).

So the user spacetime is identical to UTC.

Time zone clock and bios clock are always ok

What is a "time-zone clock" ? I have no idea what you mean.
By "bios clock" I assume you mean the hwclock. What does "ok" mean - does it mean it matches UTC or local wallclock time or something else ?

[Gareth Jones]

Do you boot Windows too, or only Linux?

Run system-config-time. Then:
1) go to the Timezone tab, and set your time-zone correctly if it isn't already;
2) if you only use Linux, set "System clock uses UTC" to on, otherwise off.

Reboot and go into BIOS. If you only use Linux, set the BIOS clock to UTC. Otherwise set it to local-time.

Boot Linux. If the time shown correctly, you can then enable network-time to synchronize the clock automatically over the Internet.

[Gareth Jones]

That should be system-config-date, not time! Sorry for the mistake.