CentOS - Feb 2008 - Installation problems with large mirrored drives

I am trying to install CentOS 4.6 to a pair of 750GB hard drives.  I can
successfully install to either of the drives as a single drive, but when
I try to use both drives and mirror the partitions, I start having
problems.  Anaconda crashes as it is trying to format the drives.

This is what I'm trying to create:

    /dev/md0: 200MB, /boot
    /dev/md1: 2GB, swap
    /dev/md2: rest of the drive, LVM PV

    LogVol00: 10GB, /
    LogVol01: rest of the VG, /home

I uploaded the anaconda log to the CentOS bugtracker, but I don't know
if or when I should expect a response from that, so I'm asking here as
well.  If you want to see the log, here's the link:
http://bugs.centos.org/view.php?id=2652

Is there a way I can work around this problem?  It has been suggested
that I build the system with a single drive and then add the mirror to
it.  Is it possible to add a mirror to a partition that is an LVM PV?
Can someone give me a link to a good set of instructions for doing this?

Thanks,

-- 
Bowie

Bowie Bailey wrote:
> Is there a way I can work around this problem?  It has been suggested
> that I build the system with a single drive and then add the mirror to
> it.  Is it possible to add a mirror to a partition that is an LVM PV?
> Can someone give me a link to a good set of instructions for doing this?
I work around it by not using LVM during installation. I've experienced
random crashes with anaconda going back to at least RHEL 3 I think when
LVM was used during install(kickstart specifically). Often times if
I try a 2nd(or a 3rd) time I can get anaconda to go through without
crashing on LVM.

If you really want LVM I'd suggest something like making your root and
boot(assuming you have seperate ones) partitions standalone mirrored
partitions, setup another pair of mirrored partitions that take up the
rest of the drive that you'll use for LVM, but don't make it LVM, just
make it a normal file system(this so it configures the software raid
end of things for you).

Once the system is installed, then change the partition type of the
last mirrored pair to be LVM, and configure LVM. If you want your
/usr /var etc on LVM make the volumes, go to runlevel 1 and copy
the files to the new locations and re-mount the LVM volumes as
your /usr /var etc.

nate

nate wrote:
> Bowie Bailey wrote:
> 
> > Is there a way I can work around this problem?  It has been
> > suggested that I build the system with a single drive and then add
> > the mirror to it.  Is it possible to add a mirror to a partition
> > that is an LVM PV? Can someone give me a link to a good set of
> > instructions for doing this? 
> 
> I work around it by not using LVM during installation. I've
> experienced random crashes with anaconda going back to at least RHEL
> 3 I think when LVM was used during install(kickstart specifically).
> Often times if 
> I try a 2nd(or a 3rd) time I can get anaconda to go through without
> crashing on LVM.
> 
> If you really want LVM I'd suggest something like making your root and
> boot(assuming you have seperate ones) partitions standalone mirrored
> partitions, setup another pair of mirrored partitions that take up the
> rest of the drive that you'll use for LVM, but don't make it LVM,
just
> make it a normal file system(this so it configures the software raid
> end of things for you).
> 
> Once the system is installed, then change the partition type of the
> last mirrored pair to be LVM, and configure LVM. If you want your
> /usr /var etc on LVM make the volumes, go to runlevel 1 and copy
> the files to the new locations and re-mount the LVM volumes as
> your /usr /var etc.
I was able to install the system with no problems using the exact same
filesystem layout (LVM and all) with a single drive.  The problem only
occurs when I try to mirror the partitions.

I may give your suggestion a try tomorrow when I have more time to play
with the system.

-- 
Bowie

Bowie Bailey wrote:
..... md, lvm, etc...


I make /boot a standalone partition as /dev/sda0  and later manually 
copy it to /dev/sdb0 which I mount as /boot2
I make a hda2 on each drive as a swap, mirrored as /dev/md1
I make a hda3 on each drive, mirror as /dev/md0, then make this a LVM, 
and all my system partitions are created in this LVM.  its messy, but it 
works.


here's some of the config of a simple dual IDE drive CentOS 5 box I 
setup for some tests...


# fdisk -l

Disk /dev/hda: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/hda1   *           1          13      104391   83  Linux
/dev/hda2              14          79      530145   82  Linux swap / Solaris
/dev/hda3              80       60801   487749465   fd  Linux raid 
autodetect

Disk /dev/hdb: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/hdb1   *           1          13      104391   83  Linux
/dev/hdb2              14          79      530145   82  Linux swap / Solaris
/dev/hdb3              80       60801   487749465   fd  Linux raid 
autodetect

# mdadm --misc --detail /dev/md0
/dev/md0:
        Version : 00.90.03
  Creation Time : Mon Jul 23 03:21:50 2007
     Raid Level : raid1
     Array Size : 487749376 (465.15 GiB 499.46 GB)
    Device Size : 487749376 (465.15 GiB 499.46 GB)
   Raid Devices : 2
  Total Devices : 2
Preferred Minor : 0
    Persistence : Superblock is persistent

    Update Time : Wed Feb  6 13:50:07 2008
          State : clean
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0

           UUID : 0b01feb0:fcd82e29:fc464a34:7e30e91a
         Events : 0.4

    Number   Major   Minor   RaidDevice State
       0       3        3        0      active sync   /dev/hda3
       1       3       67        1      active sync   /dev/hdb3

# lvm pvdisplay
  --- Physical volume ---
  PV Name               /dev/md0
  VG Name               VolGroup00
  PV Size               465.15 GB / not usable 29.75 MB
  Allocatable           yes
  PE Size (KByte)       32768
  Total PE              14884
  Free PE               284
  Allocated PE          14600
  PV UUID               w5489v-kCEo-tbY9-hwLl-GME0-x1wL-XjMSrC
  
# lvm lvdisplay
  --- Logical volume ---
  LV Name                /dev/VolGroup00/LogVol00
  VG Name                VolGroup00
  LV UUID                O7rU30-CQKO-18tJ-Vo1L-Zcxh-bOjk-00MM9C
  LV Write Access        read/write
  LV Status              available
  # open                 1
  LV Size                19.53 GB
  Current LE             625
  Segments               1
  Allocation             inherit
  Read ahead sectors     0
  Block device           253:0
  
  --- Logical volume ---
  LV Name                /dev/VolGroup00/LogVol02
  VG Name                VolGroup00
  LV UUID                CUybA0-qRDq-HYEI-fxtX-f4YU-XVST-dmoC7G
  LV Write Access        read/write
  LV Status              available
  # open                 1
  LV Size                397.66 GB
  Current LE             12725
  Segments               2
  Allocation             inherit
  Read ahead sectors     0
  Block device           253:1
  
  --- Logical volume ---
  LV Name                /dev/VolGroup00/LogVol01
  VG Name                VolGroup00
  LV UUID                hkx0s2-XaGt-WPzq-8vzS-fi3I-1z3C-MX41Uj
  LV Write Access        read/write
  LV Status              available
  # open                 1
  LV Size                39.06 GB
  Current LE             1250
  Segments               1
  Allocation             inherit
  Read ahead sectors     0
  Block device           253:2
  
# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
                       19G  1.7G   17G  10% /
/dev/hda1              99M   17M   78M  18% /boot
/dev/hdb1              99M  5.6M   89M   6% /boot1
tmpfs                 252M     0  252M   0% /dev/shm
/dev/mapper/VolGroup00-LogVol02
                      386G  291G   75G  80% /home
/dev/mapper/VolGroup00-LogVol01
                       38G  882M   36G   3% /var



and, here's the applicable anaconda-ks.cfg entries that got created at 
install time...

clearpart --linux
part /boot --fstype ext3 --size=100 --asprimary
part swap --size=520 --ondisk=hdb
part swap --size=520 --ondisk=hda --asprimary
part /boot1 --fstype ext3 --size=100 --ondisk=hdb --asprimary
part raid.4 --size=100 --grow --ondisk=hdb
part raid.3 --size=100 --grow --ondisk=hda
raid pv.6 --fstype "physical volume (LVM)" --level=RAID1 --device=md0 
raid.3 raid.4
volgroup VolGroup00 --noformat --pesize=32768 pv.6
logvol / --fstype ext3 --name=LogVol00 --vgname=VolGroup00 --size=20000
logvol /var --fstype ext3 --name=LogVol01 --vgname=VolGroup00 --size=40000
logvol /home --fstype ext3 --name=LogVol02 --vgname=VolGroup00 --size=100000


(ok, I lied, I didn't mirror my swap, I really should fix that)

Bowie Bailey wrote:
> I am trying to install CentOS 4.6 to a pair of 750GB hard drives.  I can
> successfully install to either of the drives as a single drive, but when
> I try to use both drives and mirror the partitions, I start having
> problems.  Anaconda crashes as it is trying to format the drives.
>
> This is what I'm trying to create:
>
>     /dev/md0: 200MB, /boot
>     /dev/md1: 2GB, swap
>     /dev/md2: rest of the drive, LVM PV
>
>     LogVol00: 10GB, /
>     LogVol01: rest of the VG, /home
>
>   
I have had success doing it this way on several 4.x and 5.x servers 
using Anaconda:

/dev/md0 (raid-1): /boot
/dev/md1-md?: PVs for VolGroup00

/dev/VolGroup00/LogVol00: swap
/dev/VolGroup00/LogVol01: /