10.04.1 LTS install with RAID support?

[Tom H]

On Fri, Jan 28, 2011 at 2:40 PM, Steve Malenfant <smalenfant at gmail.com> wrote:
> On Fri, Jan 28, 2011 at 2:20 PM, Tom H <tomh0665 at gmail.com> wrote:
>> On Fri, Jan 28, 2011 at 12:25 PM, Steve Malenfant <smalenfant at gmail.com>
>> wrote:
>> > On Fri, Jan 28, 2011 at 12:11 PM, Tom H <tomh0665 at gmail.com> wrote:
>> >> On Fri, Jan 28, 2011 at 12:06 PM, Steve Malenfant
>> >> <smalenfant at gmail.com>
>> >> wrote:
>> >> > On Fri, Jan 28, 2011 at 11:47 AM, Alan Pope <popey at ubuntu.com> wrote:
>> >> >> On 28 January 2011 14:38, Steve Malenfant <smalenfant at gmail.com>
>> >> >> wrote:
>> >> >>>
>> >> >> > Not yet. The problem is that I don't have any writable CD anymore.
>> >> >>
>> >> >> I specifically meant use the netinst ISO on a usb stick using
>> >> >> unetbootin. I used this last week, and believe you won't get the CD
>> >> >> mount issue because the mini/netinst iso doesn't grab packages from
>> >> >> a
>> >> >> local CD repo but from online.
>> >> >>
>> >> >> But it looks like you're sorted now :)
>> >> >>
>> >> > Sorted, not really. I believe my main problem is that these drives
>> >> > had
>> >> > already an Soft RAID config on them. I'm trying to re-purpose them.
>> >> > But
>> >> > the
>> >> > installation can't remove the RAID configuration. It would be nice to
>> >> > have
>> >> > an option to remove all RAID partitioning before the partitioning
>> >> > happen.
>> >> > Anyway, I tried removing that stuff with Gparted... failed. mdadm
>> >> > --zero-superblock fails. So.. waiting for the long dd -if=/dev/zero
>> >> > on
>> >> > them
>> >> > and hopefully this md2 array won't show up on next install!
>> >> > Is this supposed to be that complicated?
>> >>
>> >> There's no reason why
>> >> mdadm --zero-superblock <every_mdadm_partition>
>> >> wouldn't work.
>> >>
>> >> It's definitely the way to go.
>> >>
>> > I thought it was too.. But there is something you guys didn't know (I
>> > didn't
>> > either!). Well.. I tried fakeraid with the nvidia MCP... Well, it wrote
>> > something on there which dmraid detected... It asked me during the
>> > installation if I wanted to load the "SATA RAID". Of course I said "no".
>> > But
>> > the install detected it anyway. So, to remove you have to do "dmraid
>> > -rE".
>> > Just something I tried from other forums... Then it told me : Do you
>> > want to
>> > remove the tag nvidia blabla bla... That's where I knew that Nvidia RAID
>> > was
>> > interfering even after being disabled.
>> > I'm not out of the woods yet. I created my partitions manually on both
>> > drives but the "Configure software RAID" won't bring up my MD RAID1
>> > partition to assign the "/" partition and doesn't show anywhere. I'll
>> > try
>> > another reboot for that.
>>
>> "There's no reason..."! :)
>>
>> When you referred to "Soft RAID" I assumed mdraid not dmraid...
>>
>> There apparently is: dmraid's involved.
>>
>> The latest installers are pretty aggressive in using dmraid because
>> dmraid support's been bad in the past...
>>
>> dmraid's got a command similar to mdadm's "--zero-superblock";
>> "--erase-metadata"? (IIRC!)
>>
>> mdadm can now manage dmraid arrays but I guess not to the extent of
>> zeroing metadata.
>>
>> I'm downloading a server iso to install it in a VM because I don't
>> understand why you couldn't set up mdraid through the installer - and
>> I don;t see why you have to reboot for an mdraid array to be
>> recognized by d-i.

> There is because the disk were written by the nvidia MCS and mdadm did
> recognize but couldn't destroy it. I had to use dmraid to remove the
> metadata.
> I don't know... :) But it is installing slowly and syncing the Array now..
> You will probably have no problem with a brand new VM partition like I did
> here with my 1.5TB drives.
> The reboot was needed between the partionning the hard drive and creating
> the arrays. The sdaX and sdbX partition were just not available in /dev.
> Only /dev/sda and /dev/sdb were present. A reboot fixed that.

I've just gone through an mdadm install in a VirtualBox VM without a
hitch from the server iso.

Zeroing the metadata should have allowed you to be at the same state
as my blank VM disks! If not, mdadm and/or dmraid are buggy...