LVM on Raid-1 using same disks problem

6 Aug 2004

      Hello,

I have the same problem mentioned some times since 2002 in the list,
unfortunately I did not found an answer which works for me.
I am installing SLES8 through autoyast with software raid and LVM on it.
Software Raid contains two partitions (sda3 and sdb3) as I can not use
whole disks. The machine is a pSeries p690 LPAR so a PrepBoot partition is
required on each disk.
The installation worked fine for the first time, repeating the installation
on the same disks produced an error: can not create md0 device and can not
create system volume group- volume group already exists.
I am using <initialize config:type="boolean">true</initialize> in each
drive section
And  <destroy_old config:type="boolean">true</destroy_old> in lvmgroup.

I guess the problem is related to the persistent superblock used  by
software raid and VGDA on the disk used by LVM. I also tried using a
prescript:

dd if=/dev/zero of=/dev/sda bs=1MB count=3
dd if=/dev/zero of=/dev/sdb bs=1MB count=3
# this does not works:
blockdev --rereadpt /dev/sda
blockdev --rereadpt /dev/sdb

For network boot on pSeries I am using SUSE SLES8 SP3 Kernel with the
builtin commandline:  ./mkzimage_cmdline -a -1 -c -s "insmod=e100
insmod=e1000 hostip=9.156.175.22 netmask=255.255.255.0
install=nfs://9.156.175.8/software/Linux/PPC/SLES8/unpacked/CD1
autoyast=tftp://9.156.175.8/tftpboot/autoyast_tb.xml" install.tb

Unfortunately I can overwrite the begining of the disk, but rereading the
partition table fails (disc is in use message in the log). Is there any
trick how to reread the partition table or to get rid of the persistent
Superblock and VGDA before the installation starts? Now,  I need to start
installation, read the error messages about raid and lvm, restart
installation and it works fine running second time. It also works fine on a
new LPAR.

Any help is welcome..

Mit freundlichen Gruessen / Best regards,

Tomas Baublys

 IBM Certified Advanced Technical Expert (CATE)  pSeries and AIX

 pSeries Technical Sales Support
 JS20 Technical Focus Group
 Systems Sales,  Central Region

here is my autoyast control file:

root@csm:/tftpboot> cat autoyast_tb.xml
<?xml version="1.0"?>
<!DOCTYPE profile SYSTEM
"/usr/share/YaST2/include/autoinstall/profile.dtd">
<profile xmlns="http://www.suse.com/1.0/yast2ns"
xmlns:config="http://www.suse.com/1.0/configns">
  <configure>
<networking>
      <dns>
        <dhcp_hostname config:type="boolean">false</dhcp_hostname>
        <dhcp_resolv config:type="boolean">false</dhcp_resolv>
        <domain>munich.de.ibm.com</domain>
        <hostname>p690-lpar2</hostname>
        <nameservers config:type="list">
        </nameservers>
        <searchlist config:type="list">
          <search>ibm.com</search>
        </searchlist>
      </dns>
      <interfaces config:type="list">
        <interface>
          <bootproto>static</bootproto>
          <broadcast></broadcast>
          <device>eth0</device>
          <ipaddr>9.156.175.22</ipaddr>
          <module>e100</module>
          <netmask>255.255.255.0</netmask>
          <network>9.156.175.0</network>
          <options></options>
          <remote_ipaddr></remote_ipaddr>
          <startmode>onboot</startmode>
          <wireless>no</wireless>
        </interface>
      </interfaces>
      <routing>
        <ip_forward config:type="boolean">false</ip_forward>
        <routes config:type="list">
          <route>
            <destination>default</destination>
            <device>-</device>
            <gateway>9.156.175.1</gateway>
            <netmask>-</netmask>
          </route>
        </routes>
      </routing>
    </networking>

<scripts>
      <chroot-scripts config:type="list"/>
     <post-scripts config:type="list">
<script>
<filename>postinstalltasks.sh</filename>
<interpreter>shell</interpreter>
<source>
<![CDATA[
/sbin/lilo
dd if=/dev/sda1 of=/dev/sdb1
mkdir /mnt/sp3
mount 9.156.175.8:/software/Linux/PPC/SLES8/unpacked/Fixpack3-CD1 /mnt/sp3
rpm -Fvh
/mnt/sp3/ppc/update/SuSE-SLES/8/rpm/ppc/kernel-ppc64-2.4.21-111.ppc.rpm
/usr/bin/installation_sources -e -a
nfs://9.156.175.8:/software/Linux/PPC/SLES8/unpacked/Fixpack3-CD1

]]>
          </source>
        </script>

     </post-scripts>

 <pre-scripts config:type="list">
        <script>
          <filename>eliminator.sh</filename>
          <interpreter>shell</interpreter>
          <source>
<![CDATA[

vgchange -an
vgremove system
pvchange -ax
mount -t nfs 9.156.175.8:/software/Linux/PPC /mnt
/mnt/mdadm --zero-superblock /dev/sda
/mnt/mdadm --zero-superblock /dev/sdb
/mnt/mdadm -S /dev/md0
umount /mnt
vgscan
vgchange -an
vgreduce system -a -v
vgchange -a y system
lvremove -f /dev/system/usrlv
lvremove -f /dev/system/swaplv
lvremove -f /dev/system/usrlv
lvremove -f /dev/system/homelv
lvremove -f /dev/system/*
vgchange -a n system
vgremove system

dd if=/dev/zero of=/dev/sda bs=1MB count=3
dd if=/dev/zero of=/dev/sdb bs=1MB count=3
# klappt erst nach reboot
blockdev --rereadpt /dev/sda
blockdev --rereadpt /dev/sdb
]]>
          </source>
        </script>
</pre-scripts>

   </scripts>
<files config:type="list">
<config_file>
<file_path>/etc/lilo.conf</file_path>
<file_contents>
<![CDATA[
# lilo von autoyast
default=linux
timeout=100
boot=/dev/sda1
activate

image = /boot/vmlinuz
        label = linux
        root = /dev/sda2
#        initrd = /boot/initrd
        append = ""

]]>
</file_contents>
</config_file>

<config_file>
<file_path>/root2/etc/lilo.conf</file_path>
<file_contents>
<![CDATA[
# sdb lilo von autoyast
default=linux
timeout=100
boot=/dev/sdb1
activate

image = /boot/vmlinuz
        label = linux
        root = /dev/sdb2
#        initrd = /boot/initrd
        append = ""

]]>
</file_contents>
</config_file>

<config_file>
<file_path>/etc/ntp.conf</file_path>
<file_contents>
<![CDATA[
# ntp config von autoyast
server 192.53.103.103
server 192.53.103.104

]]>
</file_contents>
</config_file>

</files>
    <users config:type="list">
      <user>
        <encrypted config:type="boolean">true</encrypted>
        <user_password>XGULujbJ2KVmI</user_password>
        <username>root</username>
      </user>
    </users>

</configure>
<install>
    <bootloader>
      <location>ppc_chrp</location>

<prep_boot_partition>/dev/sda1</prep_boot_partition>
    </bootloader>
    <general>
<clock>
        <hwclock>localtime</hwclock>
        <timezone>Europe/Berlin</timezone>
      </clock>
      <keyboard>
        <keymap>german</keymap>
      </keyboard>
      <language>de_DE</language>
      <mode>
        <confirm config:type="boolean">false</confirm>
        <forceboot config:type="boolean">false</forceboot>
        <interactive_boot config:type="boolean">false</interactive_boot>
        <reboot config:type="boolean">false</reboot>
      </mode>
      <mouse>
        <id>none</id>
      </mouse>

</general>

  <partitioning config:type="list">
      <drive>
        <device>/dev/sda</device>
 <use>all</use>
<initialize config:type="boolean">true</initialize>
        <partitions config:type="list">
          <partition>
<partition_nr config:type="integer">1</partition_nr>
<partition_type>primary</partition_type>

            <crypt_fs config:type="boolean">false</crypt_fs>
            <crypt_key></crypt_key>
            <format config:type="boolean">false</format>
            <mount></mount>
            <partition_id config:type="integer">65</partition_id>
            <size>7.8MB</size>
          </partition>
<partition>
 <partition_nr config:type="integer">2</partition_nr>
<partition_type>primary</partition_type>

           <crypt_fs config:type="boolean">false</crypt_fs>
            <crypt_key></crypt_key>
            <filesystem config:type="symbol">ext3</filesystem>
            <format config:type="boolean">true</format>
            <fstopt>noatime,data=ordered</fstopt>
            <label>ROOT</label>
            <mount>/</mount>
            <mountby config:type="symbol">device</mountby>
            <partition_id config:type="integer">131</partition_id>
            <size>2GB</size>
          </partition>

 <partition>
            <crypt_fs config:type="boolean">false</crypt_fs>
            <crypt_key></crypt_key>
            <format config:type="boolean">false</format>
            <raid_name>/dev/md0</raid_name>
            <partition_id config:type="integer">253</partition_id>
            <partition_nr config:type="integer">3</partition_nr>
            <size>max</size>
          </partition>

        </partitions>
      </drive>
      <drive>
        <device>/dev/sdb</device>
 <use>all</use>
        <initialize config:type="boolean">true</initialize>
        <partitions config:type="list">

       <partition>
<partition_nr config:type="integer">1</partition_nr>
<partition_type>primary</partition_type>

            <crypt_fs config:type="boolean">false</crypt_fs>
            <crypt_key></crypt_key>
            <format config:type="boolean">false</format>
            <mount></mount>
            <partition_id config:type="integer">65</partition_id>
            <size>7.8MB</size>
          </partition>
<partition>
 <partition_nr config:type="integer">2</partition_nr>
<partition_type>primary</partition_type>

           <crypt_fs config:type="boolean">false</crypt_fs>
            <crypt_key></crypt_key>
            <filesystem config:type="symbol">ext3</filesystem>
            <format config:type="boolean">true</format>
            <fstopt>noatime,data=ordered</fstopt>
 <size>2GB</size>
<label>ROOT2</label>
            <mount>/root2</mount>
</partition>

 <partition>
            <crypt_fs config:type="boolean">false</crypt_fs>
            <crypt_key></crypt_key>
            <format config:type="boolean">false</format>
            <raid_name>/dev/md0</raid_name>
            <partition_id config:type="integer">253</partition_id>
            <partition_nr config:type="integer">3</partition_nr>
            <size>max</size>
          </partition>

        </partitions>
      </drive>
    </partitioning>

<raid config:type="list">
      <raid_device>
        <device_name>/dev/md0</device_name>
        <parity_algorithm>left-asymmetric</parity_algorithm>
        <persistent_superblock
config:type="boolean">true</persistent_superblock>
        <raid_type>raid1</raid_type>
        <lvm_group>system</lvm_group>
        <mount />
        <format config:type="boolean">false</format>
      </raid_device>
    </raid>

 <lvm config:type="list">
<lvm_group>
 <destroy_old config:type="boolean">true</destroy_old>
<lvm_name>system</lvm_name>
        <pesize>16M</pesize>
        <logical_volumes config:type="list">
          <lv>
            <lv_name>usrlv</lv_name>
            <lv_size>1GB</lv_size>
            <lv_fs>ext3</lv_fs>
            <lv_mount>/usr</lv_mount>
          </lv>
          <lv>
            <lv_name>swaplv</lv_name>
            <lv_size>512MB</lv_size>
            <lv_mount></lv_mount>
          </lv>
          <lv>
            <lv_name>varlv</lv_name>
            <lv_size>512MB</lv_size>
            <lv_fs>ext3</lv_fs>
            <lv_mount>/var</lv_mount>
          </lv>

<lv>
            <lv_name>varloglv</lv_name>
            <lv_size>512MB</lv_size>
            <lv_fs>ext3</lv_fs>
            <lv_mount>/var/log</lv_mount>
          </lv>
<lv>
            <lv_name>optlv</lv_name>
            <lv_size>512MB</lv_size>
            <lv_fs>ext3</lv_fs>
            <lv_mount>/opt</lv_mount>
          </lv>

 <lv>
            <lv_name>homelv</lv_name>
            <lv_size>512MB</lv_size>
            <lv_fs>ext3</lv_fs>
            <lv_mount>/home</lv_mount>
          </lv>

</logical_volumes>
      </lvm_group>
    </lvm>

<software>
      <base>Minimal</base>
      <packages config:type="list">
        <package>tripwire</package>
        <package>rsync</package>
        <package>xntp</package>
        <package>raidtools</package>
        <package>vim</package>
        <package>autoyast2-installation</package>
      </packages>
    </software>
  </install>
</profile>