MotherBoard without RTC battery - fake-hwclock

[peioazkarate]

Hi,

I've a Motherboard without RTC battery.
Every time I power up I need to go into the BIOS and update date and time.
Otherwise ubuntu don't start and appears the message "errors were found while checking the disk drive for /”.
I installed fake-hwclock without results.
Any idea?.

[tgalati4]

Is the battery missing? Was the motherboard designed without a battery for the real time clock (rtc)? The disk errors are a separate issue.

Look through the log files for other errors. Open a terminal.


more /var/log/syslog

Spacebar to page forward, "q" to quit.

[peioazkarate]

It's an embedded system with the RTC battery powered from a rack. When the board is extracted from the rack RTC power is lost. So the BIOS date is lost.
It's not an disk error. When the Ubuntu's init scripts detect a BIOS date previous to the last date saved on disk, launch a fsck.
fake-hwclock should be a workaround.

From fake-hwclock man:
Many embedded Linux systems do not have a functional hardware clock.
Either they simply don't have a hardware clock at all or they have a
hardware clock but it is not usable (e.g. because Linux doesn't know
how to use it or because no battery is present).

This can lead to time moving backwards to some default value (often
1970) when the system is rebooted. Since lots of software assumes that
time only moves forward this is a bad thing. NTP can (and should where
practical) be used to sync with an external timeserver but it is not
available early in the boot process and may be unavailable for other
reasons.

But it doesn't works.
I suspect the script could be launching fsck before the fake-hwclock script is executed.

Someone knows about Ubuntu's init scripts related to fsck?.

[tgalati4]

Well, there is tune2fs and some switches that may bypass the file system check and to continue on errors.


man tune2fs

Although Ubuntu can run on embedded systems, it's really not designed to. Expect some breakage and headaches.

[peioazkarate]

tune2fs doesn't solve the issue.
It seems "init" date check works apart of tune2fs parameters.

[tgalati4]

If you can't boot with tune2fs or a sysctl parameter (man sysctl), then you have no recourse except to patch the kernel to work with this hardware. Such patching is not uncommon for getting linux to work properly on embedded hardware.

And it appears that you can't completely turn off fsck for file system errors with tune2fs, so you need to determine exactly what is causing the file system errors. Normally time stamps won't, but anything is possible. Many linux systems boot just fine with a bad rtc (bad motherboard battery, super slow quartz crystal, or fried rtc), and rely on ntp to set the clock during bootup. It's possible that your embedded boards don't have a real date for the default values (like 01/01/2012) when booting.

[sinisa1hr-z]

why not just powered it,with 3V DC source(most motherboards have one 3V DC battery)..like that motherboard have it while is in rack, or make extra long extension cable so will work outside of rack ,too.. so easy workaround..regardless you still have or have not that rack..so if i understand you good,you have jack on mobo (for RTC supply input)what and from where mobo was connected to rack.. so cheapest solution is plastic battery holder(have for 3V batt,and even for 2 X AA type bat) and wire to jack or socket,or pins.. easy like that! well even power adapter ac to 3v dc can be used..but ac/dc adapter to 3vdc i do not recommend as when main ac power is lost.. really cheap hardware workaround.. some (broken)toys have battery holder and wire...so cost can be 0,and "green"...maybe photo of that socket or pins?