[Novalug] Asking early... maybe ok Fedora + HW RAID

[Michael Madore]

On Wed, Nov 25, 2009 at 9:13 PM, greg pryzby <greg at pryzby.org> wrote:
> Leaving the "boot size" blank is the secret. now it works. not sure why,
> but there you go.


Hi Greg,

What size were you setting the boot volume size to before?  The boot
volume feature is provided to work around the fact that GRUB cannot
boot off a RAID volume > 2TB in size.  This is the maximum size
supported by msdos partition tables.  To go larger than 2TB requires a
gpt partition table.  Unfortunately, GRUB cannot boot from such a
partition.

Mike Madore

> On 11/25/2009 06:53 PM, greg pryzby wrote:
>> On 11/25/2009 06:38 PM, Peter Larsen wrote:
>>> On Wed, 2009-11-25 at 17:57 -0500, greg pryzby wrote:
>>>> On 11/25/2009 04:36 PM, Peter Larsen wrote:
>>>> > On Wed, 2009-11-25 at 15:56 -0500, greg pryzby wrote:
>>>> >> I received a box w/ hardware RAID with Fedora 11. It worked great. I
>>>> >> tried to preupgrade and on reboot I got a mismatched size error. So I
>>>> >> googled to see what could be going on w/o much info. There was an
>>>> >> preupgrade in updates-testing that was recommended so I tried
>>>> that, same
>>>> >> issue. From looking at OS level, RAID looked ok.
>>>> >
>>>> > What kind of"hardware" raid? The hardware raid my box came with turned
>>>> > out to be software and a lot worse that our md drivers. The problem
>>>> you
>>>> > need to be aware of isn't whether the kernel supports it, but if grub
>>>> > supports it. Grub2 is supposed to have better support, but it's a
>>>> lousy
>>>> > documented project (it's included with Fedora - good luck is all I can
>>>> > say). I had a simple RAID0 (stripe) and grub failed miserably
>>>> > reading/understanding the raid on the system board.
>>>> >
>>>> > If you're going RAID1 you may be more lucky since it shouldn't matter
>>>> > what disk it chooses - unless there's truely a Hw raid signature on
>>>> the
>>>> > disk that'll confuse grub.
>>>>
>>>> 3ware 9650SE and it is supported in Linux, in the kernel. the crappy mb
>>>> raid isn't being used. pci-e card
>>>
>>> But is it supported by GRUB? What does Grub after phase 1 has loaded
>>> from MBR+boot?
>>
>> I don't know. I will google.
>>
>> I can tell you SLES 11 sees everything fine. ARG!
>>
>> I am not getting to GRUB yet. I am installing and it is going to look
>> for storage devices. That is when it dies in anaconda.
>>
>> This time I tried to save the trace and the whole box froze.
>>
>>
>>>> I built RAID 5 via the firmware
>>>>
>>>> However, looking at dmesg, they talk about RAID 6, ok whatever.
>>>> shouldn't matter from a quick search.
>>>
>>> THAT should not matter if it's true hardware raid. The actual raid
>>> mechanisms are hidden from the OS/boot loader.
>>
>> Agreed and ignoring
>>
>>>> There are 2 partitions (is that the right term?). it asked in firmware
>>>> about boot size and it created 2 partitions.
>>>
>>> Sure could be. Same rules applies as a single disk. You need a boot
>>> partition. And something for the rest. Grub2 allows you to place the
>>> boot on LVM2 - so you don't need any partitions then. Can't wait!
>>
>> Well, RAID setup (RAID 5) has a place to boot 'boot size'. I set that to
>> something the first time. This time I am leaving it blank. Maybe that
>> confuses the system?
>>
>> There are 5 500GB SATA drives
>>
>>> But your HW raid should NOT care at all about "partitions". If you're
>>> doing RAID 6 you have at least 4 disks of the same size and dimension.
>>> Your HW Raid should simply make a single disk-image (logical) out of the
>>> 4 disks and present this volume to the OS. The OS will then do what it
>>> usually does, with partitions and all (including MBR). In some cases,
>>> metadata about the RAID is stored on disks - but I wouldn't expect to
>>> see that in partitions. That should be hidden from you.
>>>
>>>> I think that maybe where things are wacky or maybe there is ONLY
>>>> hardware raid5 disks.
>>>
>>> The actual raid level should not matter if it's true hardware. What
>>> happened to my software card (I checked your card, it has a processor on
>>> it so it should be true hardware) was that once grub-stage 1 was over,
>>> it couldn't find the partition and it's data to boot from.
>>
>> Off to look at grub, but like i said it isn't getting that far... just
>> trying to find the storage disk
>>
>> 3w_9xxx is loaded (driver for 3ware card)
>>
>> I hope by not setting boot size and taking all default setting for the
>> RAID creation, it will work better.
>>
>>
>
>
> --
> greg at pryzby dot org
> http://www.linkedin.com/in/gpryzby
> BLOG: http://restonartistree.blogspot.com/
> WEB:  http://www.RestonArtisTree.com/
> TWTR: gpryzby
> _______________________________________________
> Novalug mailing list
> Novalug at calypso.tux.org
> http://calypso.tux.org/mailman/listinfo/novalug
>