Boot-up results in a read-only root drive

Somehow, the wife got her laptop into this situation yesterday. The Windows
partition booted normally when selected from GRUB but os 11.3 would boot to
a command line login and pretty much everything besides CTRL-D was useless
as the root partition was ro.

I booted a live CD and found two a couple of strange things. First, the
system clock was reset to the default date/time (2007-xx-xx). I reset that.

Second, after correcting the time I ran fsck on the root and home
partitions. Both went through with no errors reported but the 20GB root
partition took a long,long time to complete while the 80GB home partition
went pretty quickly.

After doing the above, the system booted normally but both partitions
reported running the transaction log as well as forcing fsck where I had
just done that.

My question is for future reference: how does the system react to a grossly
incorrect date/time, especially where all the drive data reports being much
later than the reported system time? Would this be the reason for what I
saw?

I have no idea how the wife managed to reset the system clock, even if the
battery was totally drained but it happened. All is well now but I’d like to
be prepared for any repeat.


Will Honea

On 2011-05-20 23:41, Will Honea wrote:
> Somehow, the wife got her laptop into this situation yesterday. The Windows
> partition booted normally when selected from GRUB but os 11.3 would boot to
> a command line login and pretty much everything besides CTRL-D was useless
> as the root partition was ro.

Rescue login, right. You have to go back a little in the display (^PgUp)
and the error will be displayed, albeit often confusedly.

> I booted a live CD and found two a couple of strange things. First, the
> system clock was reset to the default date/time (2007-xx-xx). I reset that.
>
> Second, after correcting the time I ran fsck on the root and home
> partitions. Both went through with no errors reported but the 20GB root
> partition took a long,long time to complete while the 80GB home partition
> went pretty quickly.

More files in one than the other, probably. Or different types.

> After doing the above, the system booted normally but both partitions
> reported running the transaction log as well as forcing fsck where I had
> just done that.

Yep.

> My question is for future reference: how does the system react to a grossly
> incorrect date/time, especially where all the drive data reports being much
> later than the reported system time? Would this be the reason for what I
> saw?

Yes, ext3 does that, IIRC. But maybe there was something else

> I have no idea how the wife managed to reset the system clock, even if the
> battery was totally drained but it happened. All is well now but I’d like to
> be prepared for any repeat.

A low battery can cause that. Or a bump to the motherboard: the vibration
could cause the battery (plus dirt/rust) to move a bit and loose contact
for a split second, resetting the clock. But it would not be only the
clock, the entire bios config would reset.

If it happens, look carefully at the messages. Clues are there, but often
not clearly.


Cheers / Saludos,

Carlos E. R.
(from 11.2 x86_64 “Emerald” at Telcontar)

Carlos E. R. wrote:

> A low battery can cause that. Or a bump to the motherboard: the vibration
> could cause the battery (plus dirt/rust) to move a bit and loose contact
> for a split second, resetting the clock. But it would not be only the
> clock, the entire bios config would reset.

Good point! If I can get her off the machine I need to recheck the rest of
the BIOS setup - never occured to me to go through it as I reset the time
from Windows when I booted it as quick and dirty disk test.


Will Honea