Re: I am an idiot.

[Alex Boag-Munroe <boagenator@gmail.com>]

On 4 March 2010 12:22, Alex Boag-Munroe <boagenator@gmail.com> wrote:
> On 4 March 2010 12:01, John Robinson <john.robinson@anonymous.org.uk> wrote:
>> On 04/03/2010 11:30, Alex Boag-Munroe wrote:
>>>
>>> Hi guys...
>>>
>>> Yes I am an idiot.  I was changing the chunk size of my RAID5 array
>>> last night from 64kb to 256kb and left it running overnight.  During
>>> the night we had a power outage.
>>>
>>> This is where the idiot part comes in.  The backup file is on a
>>> filesystem that's part of the RAID5 array, so obviously I am unable to
>>> start it.  I completely forgot the filesystem I specified for
>>> --backup-file was part of the same array.
>>>
>>> Once you're all done pointing and laughing, can you let me know if I
>>> am totally screwed?  I've a lot of data here that I -really- don't
>>> want to lose...
>>>
>>> Please help..
>>>
>>> Idiot.
>>>
>>> --
>>> Alex Boag-Munroe
>>>
>>> Lack of planning on your part does not constitute an emergency on mine.
>>
>> OK, I was done pointing and laughing, until I saw your signature. Did you
>> choose that on purpose or did Gmail pick it for you?
>>
>> I'm afraid I can't help with your problem, except to say that I've a feeling
>> you ought to be able to manually restart the half-reshaped array without the
>> backup file, so the worst case ought to be that you might lose one backup
>> file's worth of data. However, kernel and mdadm versions together with
>> output of `mdadm --detail` of your md device and `mdadm --examine` of its
>> constituent devices will help those more knowledgeable than me tell you what
>> to do next. If you're lucky the boss, Neil Brown, will help but I imagine
>> he's asleep right now since he lives in Australia and it's the middle of the
>> night there.
>>
>> Best of luck,
>>
>> John.
>>
>
> Hi John, thanks so much for your reply.
>
> That is my signature and I stand by it, hence the whole "me idiot" and
> not DEMANDING I get help etc.
>
> mdadm is version 3.1.1.  New developments.  I found a post on the
> internet where Neil recommended to someone to recreate the array
> without erasing it.  Which I have done, mdadm starts the array and
> mdadm -D shows that almost a terabyte of space is in use.
>
> However, mdadm -D also shows a chunk size of 512k, which is neither
> the 64k original chunk nor the 512k I asked for.
>
> Kernel version is gentoo-sources-2.6.33.
>
> Output of mdadm --examine for /dev/sda5 through /dev/sdd5:
>
> /dev/sda5:
>          Magic : a92b4efc
>        Version : 0.90.00
>           UUID : 17862986:014cb4c0:ffe6e849:786ed339 (local to host ncc-1701-e)
>  Creation Time : Thu Mar  4 13:10:24 2010
>     Raid Level : raid5
>  Used Dev Size : 974767616 (929.61 GiB 998.16 GB)
>     Array Size : 2924302848 (2788.83 GiB 2994.49 GB)
>   Raid Devices : 4
>  Total Devices : 4
> Preferred Minor : 1
>
>    Update Time : Thu Mar  4 13:10:29 2010
>          State : clean
>  Active Devices : 4
> Working Devices : 4
>  Failed Devices : 0
>  Spare Devices : 0
>       Checksum : b951290 - correct
>         Events : 3
>
>         Layout : left-symmetric
>     Chunk Size : 512K
>
>      Number   Major   Minor   RaidDevice State
> this     0       8        5        0      active sync   /dev/sda5
>
>   0     0       8        5        0      active sync   /dev/sda5
>   1     1       8       21        1      active sync   /dev/sdb5
>   2     2       8       37        2      active sync   /dev/sdc5
>   3     3       8       53        3      active sync   /dev/sdd5
> /dev/sdb5:
>          Magic : a92b4efc
>        Version : 0.90.00
>           UUID : 17862986:014cb4c0:ffe6e849:786ed339 (local to host ncc-1701-e)
>  Creation Time : Thu Mar  4 13:10:24 2010
>     Raid Level : raid5
>  Used Dev Size : 974767616 (929.61 GiB 998.16 GB)
>     Array Size : 2924302848 (2788.83 GiB 2994.49 GB)
>   Raid Devices : 4
>  Total Devices : 4
> Preferred Minor : 1
>
>    Update Time : Thu Mar  4 13:10:29 2010
>          State : clean
>  Active Devices : 4
> Working Devices : 4
>  Failed Devices : 0
>  Spare Devices : 0
>       Checksum : b9512a2 - correct
>         Events : 3
>
>         Layout : left-symmetric
>     Chunk Size : 512K
>
>      Number   Major   Minor   RaidDevice State
> this     1       8       21        1      active sync   /dev/sdb5
>
>   0     0       8        5        0      active sync   /dev/sda5
>   1     1       8       21        1      active sync   /dev/sdb5
>   2     2       8       37        2      active sync   /dev/sdc5
>   3     3       8       53        3      active sync   /dev/sdd5
> /dev/sdc5:
>          Magic : a92b4efc
>        Version : 0.90.00
>           UUID : 17862986:014cb4c0:ffe6e849:786ed339 (local to host ncc-1701-e)
>  Creation Time : Thu Mar  4 13:10:24 2010
>     Raid Level : raid5
>  Used Dev Size : 974767616 (929.61 GiB 998.16 GB)
>     Array Size : 2924302848 (2788.83 GiB 2994.49 GB)
>   Raid Devices : 4
>  Total Devices : 4
> Preferred Minor : 1
>
>    Update Time : Thu Mar  4 13:10:29 2010
>          State : clean
>  Active Devices : 4
> Working Devices : 4
>  Failed Devices : 0
>  Spare Devices : 0
>       Checksum : b9512b4 - correct
>         Events : 3
>
>         Layout : left-symmetric
>     Chunk Size : 512K
>
>      Number   Major   Minor   RaidDevice State
> this     2       8       37        2      active sync   /dev/sdc5
>
>   0     0       8        5        0      active sync   /dev/sda5
>   1     1       8       21        1      active sync   /dev/sdb5
>   2     2       8       37        2      active sync   /dev/sdc5
>   3     3       8       53        3      active sync   /dev/sdd5
> /dev/sdd5:
>          Magic : a92b4efc
>        Version : 0.90.00
>           UUID : 17862986:014cb4c0:ffe6e849:786ed339 (local to host ncc-1701-e)
>  Creation Time : Thu Mar  4 13:10:24 2010
>     Raid Level : raid5
>  Used Dev Size : 974767616 (929.61 GiB 998.16 GB)
>     Array Size : 2924302848 (2788.83 GiB 2994.49 GB)
>   Raid Devices : 4
>  Total Devices : 4
> Preferred Minor : 1
>
>    Update Time : Thu Mar  4 13:10:29 2010
>          State : clean
>  Active Devices : 4
> Working Devices : 4
>  Failed Devices : 0
>  Spare Devices : 0
>       Checksum : b9512c6 - correct
>         Events : 3
>
>         Layout : left-symmetric
>     Chunk Size : 512K
>
>      Number   Major   Minor   RaidDevice State
> this     3       8       53        3      active sync   /dev/sdd5
>
>   0     0       8        5        0      active sync   /dev/sda5
>   1     1       8       21        1      active sync   /dev/sdb5
>   2     2       8       37        2      active sync   /dev/sdc5
>   3     3       8       53        3      active sync   /dev/sdd5
>
> Booting with autodetecting raid, states that there's no valid 0.9 superblock.
>
> --
> Alex Boag-Munroe
>
> Lack of planning on your part does not constitute an emergency on mine.
>

Oops. Where I said "it isn't the 512k chunk I asked for" I meant 256k chunk.

Thanks again

-- 
Alex Boag-Munroe

Lack of planning on your part does not constitute an emergency on mine.
--
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