You need to step back and appreciate that the manner in which you are  
presenting Solaris with disks is the problem and not necessarily ZFS.

As your storage system is incapable of JBOD operation, you have  
decided to present each disk as a 'simple' RAID0 volume. Whilst this  
looks like a 'pass-thru' access method to the disk and its contents,  
it is far from it. The HW RAID sub-system is creating a logical volume  
based on this single spindle (in exactly the same way it would be for  
multiple spindles, aka a stripe), metadata is recorded by the RAID  
system with regard to the make-up of said volume.

The important issue here is that you have a non-redundant RAID (!)  
config, hence a single failure (in this case your single spindle  
failure) causes the RAID sub-system to declare the volume (and hence  
its operational status) as failed, this in turn is declared to the OS  
as a failed volume. At this juncture, intervention is normally  
necessary to re-destroy/re-create a volume (remember no redundancy--- 
so this is manual!) and hence re-present it to the OS (which will find  
a new UID for the volume and treat it as a new device). On occasions  
it may be possible to intervene and "resurrect" a volume by manually  
overriding the status of the RAID0 volume, but in many HW RAID systems  
this is not to be recommended.

In short, you've got more abstractions (layers) in place than you need/ 
desire and that is fundamentally the cause of your problem ... either  
plump for a simpler array or swallow some loss of transparency in the  
ZFS layer and present redundant RAID sets from your array, but live  
with the consequences of increased admin and complexity and some loss  
of transparency/protection---but hopefully the RAID sub-system will be  
capable of automated recovery in most circumstances of simple failures.

Craig

On 27 Jan 2009, at 13:00, Edmund White wrote:

> I'm testing the same thing on a DL380 G5 with P400 controller. I set
> individual RAID 0 logical drives for each disk. I ended up with the  
> same
> result upon drive removal. I'm looking into whether the hpacucli array
> command line utility will let me re-enable a logical drive from its
> interface.
>
> -- 
> Edmund William White
> ewwh...@mac.com
>
>
>
>> From: Alex <a...@pancentric.com>
>> Date: Tue, 27 Jan 2009 04:16:56 -0800 (PST)
>> To: <zfs-discuss@opensolaris.org>
>> Subject: [zfs-discuss] Problems using ZFS on Smart Array P400
>>
>> I am having trouble getting ZFS to behave as I would expect.
>>
>> I am using the HP driver (cpqary3) for the Smart Array P400 (in a  
>> HP Proliant
>> DL385 G2) with 10k 2.5" 146GB SAS drives. The drives appear  
>> correctly, however
>> due to the controller not offering JBOD functionality I had to  
>> configure each
>> drive as a RAID0 logical drive.
>>
>> Everything appears to work fine, the drives are detected and I  
>> created a
>> mirror for the OS to install to and an additional raidz2 array with  
>> the
>> remaining 6 discs.
>>
>> But when I remove a disc and then reinsert it I cannot get ZFS to  
>> accept it
>> back into the array see bellow for the details.
>>
>> I thought it might be a problem with using the whole discs eg:  
>> c1t*d0 so I
>> created a single partition on each and used that, but had the same  
>> results.
>> The module seem to detect the drive has been reinserted  
>> successfully but the
>> OS doesn't seem to want to write to it.
>>
>> Any help would be most appreciated as I would much prefer to use  
>> ZFS's
>> software capabilities rather than the hardware card in the machine.
>>
>> When rebooting the system the Array BIOS also displays some  
>> interesting
>> behavior.
>>
>> ### BIOS Output
>>
>> 1792-Slot 1 Drive Array - Valid Data Found in the Array Accelerator
>> Data will automatically be written to the drive array
>> 1779-Slot 1 Drive Array - Replacement drive(s) detected OR  
>> previously failed
>> drives(s) no appear to be operational
>> POrt 2I: Box1: Bay3
>> Logical drives(s) disabled due to possible data loss.
>> Select "F1" to continue with logical drive(s) disabled
>> Select "F2" to accept data loss and to re-enable logical drive(s)
>>
>> #### Terminal output
>>
>> bash-3.00# zpool status test
>>
>> pool: test
>> state: DEGRADED
>> status: One or more devices could not be opened. Sufficient  
>> replicas exist for
>> the pool to continue functioning in a degraded state.
>> action: Attach the missing device and online it using 'zpool online'.
>> see: http://www.sun.com/msg/ZFS-8000-2Q
>> scrub: resilver completed after 0h0m with 0 errors on Tue Jan 27  
>> 03:30:16 2009
>> config:
>>
>> NAME STATE READ WRITE CKSUM
>> test DEGRADED 0 0 0
>> raidz2 DEGRADED 0 0 0
>> c1t2d0p0 ONLINE 0 0 0
>> c1t3d0p0 ONLINE 0 0 0
>> c1t4d0p0 ONLINE 0 0 0
>> c1t5d0p0 UNAVAIL 0 0 0 cannot open
>> c1t6d0p0 ONLINE 0 0 0
>> c1t8d0p0 ONLINE 0 0 0
>>
>> errors: No known data errors
>> bash-3.00# zpool online test c1t5d0p0
>> warning: device 'c1t5d0p0' onlined, but remains in faulted state
>> use 'zpool replace' to replace devices that are no longer present
>>
>> bash-3.00# dmesg
>>
>> Jan 27 03:27:40 unknown cpqary3: [ID 823470 kern.notice] NOTICE:  
>> Smart Array
>> P400 Controller
>> Jan 27 03:27:40 unknown cpqary3: [ID 823470 kern.notice] Hot-plug  
>> drive
>> inserted, Port: 2I Box: 1 Bay: 3
>> Jan 27 03:27:40 unknown cpqary3: [ID 479030 kern.notice] Configured  
>> Drive ?
>> ....... YES
>> Jan 27 03:27:40 unknown cpqary3: [ID 100000 kern.notice]
>> Jan 27 03:27:40 unknown cpqary3: [ID 823470 kern.notice] NOTICE:  
>> Smart Array
>> P400 Controller
>> Jan 27 03:27:40 unknown cpqary3: [ID 834734 kern.notice] Media  
>> exchange
>> detected, logical drive 6
>> Jan 27 03:27:40 unknown cpqary3: [ID 100000 kern.notice]
>> ...
>> Jan 27 03:36:24 unknown scsi: [ID 107833 kern.warning] WARNING:
>> /p...@38,0/pci1166,1...@10/pci103c,3...@0/s...@5,0 (sd6):
>> Jan 27 03:36:24 unknown SYNCHRONIZE CACHE command failed (5)
>> ...
>> Jan 27 03:47:58 unknown scsi: [ID 107833 kern.warning] WARNING:
>> /p...@38,0/pci1166,1...@10/pci103c,3...@0/s...@5,0 (sd6):
>> Jan 27 03:47:58 unknown drive offline
>> -- 
>> This message posted from opensolaris.org
>> _______________________________________________
>> zfs-discuss mailing list
>> zfs-discuss@opensolaris.org
>> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
>
>
> _______________________________________________
> zfs-discuss mailing list
> zfs-discuss@opensolaris.org
> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss

-- 
Craig

Craig Morgan
t: +44 (0)791 338 3190
f: +44 (0)870 705 1726
e: craig.mor...@sun.com

~ 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  NOTICE:  This email message is for the sole use of the intended
  recipient(s) and may contain confidential and privileged information.
  Any unauthorized review, use, disclosure or distribution is  
prohibited.
  If you are not the intended recipient, please contact the sender by
  reply email and destroy all copies of the original message.
~ 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~



_______________________________________________
zfs-discuss mailing list
zfs-discuss@opensolaris.org
http://mail.opensolaris.org/mailman/listinfo/zfs-discuss

Reply via email to