Re: Hammer Core Dumped on DragonFly v2.13.0.154.g481b38-DEVELOPMENT

[Francois Tigeot <ftigeot@xxxxxxxxxxxx>]

Hi,

On Mon, Nov 14, 2011 at 01:17:24PM +0530, Siju George wrote:
> 
> After praying in Tongues I rebooted again :-)
> 
> Data is back safe!
> 
> Is there something special about the re boot just after a core dump?

The dumped core is usually read from the swap area and put in a file; besides
that boot proceeds normally.

> Just wondering why this didn't come up straight the first time
[...]
> earlier it was
[...]
> > # undo -i 2011-11-11-all.sql.bz2
> > 2011-11-11-all.sql.bz2: ITERATE ENTIRE HISTORY: Inappropriate ioctl for device
[...]
> Could some one give the explanation?

The first problem was caused by a hardware failure, the WRITE_DMA48 lines in
your first mail:

> >> ad8: FAILURE - WRITE_DMA48 status=51<READY,DSC,ERROR> error=4<ABORTED>
> >> LBA=890156672
> >> HAMMER(): Critical error inode=-1 error=5 while flushing meta-data
> >> HAMMER(): Forcing read-only mode
> >> ad8: FAILURE - WRITE_DMA48 status=51<READY,DSC,ERROR> error=4<ABORTED>
> >> LBA=890935168

There's not much Hammer can do in this situation; the strange behavior you
saw is consistent with a drive failing to respond and then becoming available
again.

I would check the power supply and the drive itself, and be sure to have the
data backuped elsewhere if I was in your shoes.

-- 
Francois Tigeot