Re: Grub2 reinstall on raid1 system. Corrections!!!!!
On Sun, 16 Jan 2011 18:42:49 -0700
Bob Proulx <email@example.com> wrote:
> With your pastebin information and the mdstat information (that last
> information in your mail and pastebins was critical good stuff) and
> I found this old posting from you too: :-)
> With all of that I deduce the following:
> /dev/md125 /dev/sda1 /dev/sdc1 (10G) root partition with no lvm
> /dev/md126 /dev/sda5 /dev/sdc5 (288G) LVM for /home, /var, swap, ...
> /dev/md127 /dev/sdb /dev/sdd (465G) as yet unformatted
> Jack, If that is wrong please correct me. But I think that is right.
That is Exactly correct.
> The mdstat data showed that the arrays are sync'd. The UUIDs are as
> ARRAY /dev/md/125_0 metadata=0.90
> UUID=e45b34d8:50614884:1f1d6a6a:d9c6914c ARRAY /dev/md/126_0
> metadata=0.90 UUID=c06c0ea6:5780b170:ea2fd86a:09558bd1
> ARRAY /dev/md/Speeduke:2 metadata=1.2 name=Speeduke:2
> The desired state:
> /dev/md0 /dev/sda1 /dev/sdc1 (10G) root partition with no lvm
> /dev/md1 /dev/sda5 /dev/sdc5 (288G) LVM for /home, /var, swap, ...
> Will get to /dev/md2 later...
> > My thinking is that I should rerun mdadm and reassemble the arrays
> > to the original definitions... /md0 from sda1 & sdc1
> > /md1 from sda5 & sdc5 note: sda2
> > &sdc2 are legacy msdos extended partitions.
> > I would not build a md device with msdos extended partitions under
> > LVM2 at this time.. Agree?
> Agreed. You want to rename the arrays. Don't touch the msdos
> > Is the above doable? If I can figure the right mdadm commands...8-)
> Yes. It is doable. You can rename the array. First stop the array.
> Then assemble it again with the new desired name. Here is what you
> want to do. Tom, Henrique, others, Please double check me on these.
> mdadm --stop /dev/md125
> mdadm --assemble /dev/md0 --update=super-minor /dev/sda1 /dev/sdc1
> mdadm --stop /dev/126
> mdadm --assemble /dev/md1 --update=super-minor /dev/sda5 /dev/sdc5
> That should by itself be enough to get the arrays going.
> But, and this is an important but, did you previously add the new disk
> array to the LVM volume group on the above array? If so then you are
> not done yet. The LVM volume group won't be able to assemble without
> the new disk. If you did then you need to fix up LVM next.
NO! I did NOT add /dev/sdb and /dev/sdd to the LVM.. So that is not a
problem.. I was about to do that when the machine failed..
> I think you should try to get back to where you were before when your
> system was working. Therefore I would remove the new disks from the
> LVM volume group. But I don't know if you did or did not add it yet.
> So I must stop here and wait for further information from you.
> I don't know if your rescue disk has lvm automatically configured or
> not. You may need to load the device mapper module dm_mod. I don't
> know. If you do then here is a hint:
> modprobe dm_mod
> To scan for volume groups:
Found volume group "Speeduke" using metadata type lvm2
> To activate a volume group:
> vgchange -ay
5 logical volume(s) in volume group "Speeduke" now active
> To display the physical volumes associated with a volume group:
PV Name /dev/md126
VG Name Speeduke
Other data ommited
PV UUID kUoBgV-R9n6-exZ1-fdIk-aqlb-7Ue1-R3B1PD
> If the new disks haven't been added to the volume group (I am hoping
> not) then you should be home free. But if they are then I think you
> will need to remove them first.
> I don't know if the LVM actions above are going to be needed. I am
> just trying to proactively give some possible hints.
Bob, You cannot know how much I appreciate the time and effort you
and others have given to this, hopefully a few more steps and all will
I have not done the things you have suggested above. I'll wait for your
response and then go!!!
One other thing I am bothered by, md0, md1 were built using mdadm
v0.90, md2 was built with the current mdadm v 3.1.4. which changed
the md names. Does this matter????