gstripe/gpart problems.

[Daniel Braniss]

> On Tue, Jan 04, 2011 at 04:21:31PM +0200, Daniel Braniss wrote:
> > Hi,
> > I have 2 ada disks striped:
> > 
> > # gstripe list
> > Geom name: s1
> > State: UP
> > Status: Total=2, Online=2
> > Type: AUTOMATIC
> > Stripesize: 65536
> > ID: 2442772675
> > Providers:
> > 1. Name: stripe/s1
> >    Mediasize: 1000215674880 (932G)
> >    Sectorsize: 512
> >    Stripesize: 65536
> >    Stripeoffset: 0
> >    Mode: r0w0e0
> > Consumers:
> > 1. Name: ada0
> >    Mediasize: 500107862016 (466G)
> >    Sectorsize: 512
> >    Mode: r0w0e0
> >    Number: 0
> > 2. Name: ada1
> >    Mediasize: 500107862016 (466G)
> >    Sectorsize: 512
> >    Mode: r0w0e0
> >    Number: 1
> > 
> > boot complains:
> > 
> > GEOM_STRIPE: Device s1 created (id=2442772675).
> > GEOM_STRIPE: Disk ada0 attached to s1.
> > GEOM: ada0: corrupt or invalid GPT detected.
> > GEOM: ada0: GPT rejected -- may not be recoverable.
> > GEOM_STRIPE: Disk ada1 attached to s1.
> > GEOM_STRIPE: Device s1 activated.
> > 
> > # gpart show
> > =>        34  1953546173  stripe/s1  GPT  (932G)
> >           34         128          1  freebsd-boot  (64K)
> >          162  1953546045             - free -  (932G)
> > # gpart show
> > =>        34  1953546173  stripe/s1  GPT  (932G)
> >           34         128          1  freebsd-boot  (64K)
> >          162  1953546045             - free -  (932G)
> > 
> > # gpart add -t freebsd-ufs -s 20g stripe/s1
> > GEOM: ada0: corrupt or invalid GPT detected.
> > GEOM: ada0: GPT rejected -- may not be recoverable.
> > stripe/s1p2 added
> > # gpart show
> > =>        34  1953546173  stripe/s1  GPT  (932G)
> >           34         128          1  freebsd-boot  (64K)
> >          162    41943040          2  freebsd-ufs  (20G)
> >     41943202  1911603005             - free -  (912G)
> > 
> > if I go the MBR road, all seems ok, but as soon as I try to write
> > the boot block (boot0cfg -B /dev/stripe/s1) again the kernel
> > starts to complain about corrupted GEOM too.
> 
> So are you trying to partition the drives and then stripe the
> partitions within the drives, or are you trying to partition the
> stripe?
> 
> It seems here as though you might be trying to first partition the
> drives (not clear on that) then stripe the whole drives - which will
> mean the partition info is wrong for the resulting striped drive set -
> and then repartition the striped drive set, and neither is ending up
> valid.
> 
> If what you are intending is to partition after striping the raw
> drives, then you are doing the right steps, but when the geom layer
> tries to look at the info on the individual drives as at boot, it will
> find it invalid.  If it the gpart layer is actually refusing to write
> partition info to the drives which is wrong for the drives taken
> individually, that would account for your problems.
> 
> One valid order to do things in would be partition the drives with
> gpart, creating identical sets of partitions on both drives, then
> stripe the partitions created within them (syntax not exact):
>  
> gpart add -t freebsd-ufs0 -s 10g ada0
> gpart add -t freebsd-ufs1 -s 10g ada1
> gstripe label freebsd-ufs freebsd-ufs0 freebsd-ufs1
> 
> That would give you a 20GB stripe, with valid partition info on each
> drive.
> 
> If this will be your boot drive, depending on how much needs to be read
> from the drive before the geom_stripe kernel module gets loaded, I
> would think there could also be a problem booting from the drive.  This
> is not like gmirroring two drives or partitions, where the info read
> from either disk early in boot will be identical, and identical (except
> for the last block of the partition) to what the OS sees later after
> the mirror is formed.
> 
> I assume you're bearing in mind that if you lose either drive to a
> hardware fault you lose the whole thing, and consider the risk worth
> the potential speed/size gain.
>   -- Clifton 

Hi Clifton,
I was getting very frustrated yesterday, hence the cripted message, your
response requieres some background :-)
the box is a Sun Fire X2200, which has bays for 2 disks, (we have several of 
these)
before the latest upgrade, the 2 disks were 'raided' via 'nVidia MediaShield' 
and
appeared as ar0, when I upgraded to 8.2, it disappeared, since I had in the 
kernel config file
ATA_CAM. So I starded fiddling with gstripe, which 'recoverd' the data.
Next, since the kernel boot kept complaining abouf GEOM errors, (and not 
wanting to
mislead the operators) I cleaned up the data, and started from scratch.
the machine boots diskless, but I like to keep a root bootable partition just 
in case.
the process was in every case the same, first the stripe, then gpart the 
stripe.
btw, I know that if I loose a disk I lose everything. Also that I wont be able 
to boot from
it (I can always boot via the net, and mount the root localy, or some other 
combination - USB, etc)
But you gave me some ideas and will start experimenting soon.

thanks,
	danny