Re: did gbde on swap destroy some boot sectors? (and cdrom did not boot and pppoe broken in xl-driver)

From: Allan Fields <bsd_at_afields.ca>
Date: Fri, 23 Jul 2004 12:01:37 -0400
On Fri, Jul 23, 2004 at 06:30:54AM +0200, Eugene wrote:
> what can be more evil than a crash?

I agree.

> the system didnt came up again... what i saw was "F1 FreeBSD"... and 
> that it was... at first i guessed my keyboard is ugly, changed it, 
> booted and such actions... nothing...
>
> ok... so lets try to fix and boot from cd... -current cd in drive... but 
> [..] 
> so now i was surprised the boot floppy pack of -current worked fine... 
> 
> ok... im in with a fixit floppy and tried to boot the /-partition... 
> doesnt work... to mount /usr works fine... ok... lets try mount -f on 
> /... works fine... ok...
> 
> but i dint find a way to fix the bootloader or whatever was trashed... 
> so i endet up reinstalling it, lost my disklabels...a nd because it was 

Easier done directly with disklabel and/or boot0cfg.

> 6 am and i was tired i did newfs when readding the disklabels *g*... 
> last but not least... the gbde lock file was lost that way, so my other 
> partitions are useless now too... and i have much free hard drive space 
> now :-))

Unfortunately, you're not alone in having this occur.. :(

If anything is currently very important on disk and you haven't
newfs'ed the gbde partition, dd to another drive or pull this drive;
with faint hope someday you will be able to get it back (but not
holding your breath).  The more likely case is the lock file still
intact, but that may not be so.

Read back in lists for similar situation w/ lost lock-file.


[Obligatory post-mortem analysis:]

The first thing to remember in situations like this is: optimally,
don't write to the disk until you spend time dding/dumping specific
areas in interest or carefully consider all possible cases.  (Probably
biggest data loss is the cascading of problems due to being
rushed/tired, which has happened to many of us..)

It can't be stressed enough how important it is to keep lock-selector
file backup on another disk.  When one file lost is the whole file
system, it makes the case for extra prudence.  The other idea is store
this on a removable media such as flash, not in root partition.

From the Handbook (-- people have fair warning for this):
	The gbde init command creates a lock file for your gbde
	partition that in this example is stored as /etc/gbde/ad4s1c.

	Caution: gbde lock files must be backed up together with
	the contents of any encrypted partitions. While deleting a
	lock file alone cannot prevent a determined attacker from
	decrypting a gbde partition, without the lock file, the
	legitimate owner will be unable to access the data on the
	encrypted partition without a significant amount of work
	that is totally unsupported by gbde(8) and its designer.

Perhaps the handbook should now explicitly list making a lock-selector
file backup to floppy in procedure for gbde init?


> but now what happened? why couldnt it boot again?! the last thing i did 
> was enabling gbde encryption on my swaps... and swap are the first label 
> on each of the 3 drives...
> 
> i suspect gbde on swap broke something...
>
> im i wrong or can someone check this please?

It's definitely something to look at.. I can't imagine why this
should happen, except disklabel issue: where was the swap located
and what letter?  Did it happen the same on 3 drives?  If no, were
the disklabels the same?


> Eugene

-- 
 Allan Fields, AFRSL - http://afields.ca
 2D4F 6806 D307 0889 6125  C31D F745 0D72 39B4 5541

Received on Fri Jul 23 2004 - 14:01:38 UTC

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