• Centos4Yuminstallation

Centos EL 4.4 domU installation for Xen using Yum

requirements

• minimum of 700M free disc space (based on core group install only)
• network connectivity for remote repositorys

using LVM Backend for Disc

• create a Logical Volume for the domU (assume Volume Groupname is Grp_XEN)

  $ lvcreate -L 700M -n Centos4domU Grp_XEN

• create the filesystem of your choice (default ext3)

  $ mkfs.ext3 /dev/Grp_XEN/Centos4domU

• mount the file system

  $ mount /dev/Grp_XEN/Centos4domU /mnt

using Filebased Backend for Disc

• create an empty file for the device

  $ dd if=/dev/zero of=Centos4domU bs=1M count=700

• create the filesystem of your choice (default ext3)

  $ mkfs.ext3 Centos4domU

• mount the file system

  $ mount -o loop Centos4domU /mnt

create necessary directorys and layouts for installation

• $ mkdir -p /mnt/etc/yum.repos.d /mnt/proc /mnt/var/lock/rpm /mnt/dev

  $ for i in console null zero random ; do MAKEDEV -d /mnt/dev -x ${i} ; done

  $ mount -t proc none /mnt/proc

• add root useraccount from domU

  $ head -1 /etc/passwd > /mnt/etc/passwd

  $ head -1 /etc/shadow > /mnt/etc/shadow && chmod 0400 /mnt/etc/shadow

• create fstab for domU (copy&paste adds empty lines to your fstab file, remove them)

  $ cat <<EOF> /mnt/etc/fstab

  /dev/sda1 / ext3 defaults 1 1

  none /dev/pts devpts gid=5,mode=620 0 0

  none /proc proc defaults 0 0

  none /sys sysfs defaults 0 0

  EOF

• copy the Yum configs from your existing Centos installation or from the centos website

  $ wget -O /mnt/etc/yum.repos.d/Centos-Base.repo http://isoredirect.centos.org/centos/4/CentOS-Base.repo

• modify the Repo config by editing the strings '$releasever' and '$basearch' to reflect your needs
  • (for Centos 4.4 and Arch i386)

  $ sed -e " s#\$releasever#4#; s#\$basearch#i386#g; " < /mnt/etc/yum.repos.d/Centos-Base.repo > /mnt/etc/yum.repos.d/Centos-Base \

  && mv /mnt/etc/yum.repos.d/Centos-Base /mnt/etc/yum.repos.d/Centos-Base.repo

• install Centos using yum components 'Group Core'

  $ yum -y --installroot=/mnt groupinstall core

if you don't know which groups or components you want to install you can get a list (in XML) from the repositorys by calling

• $ yum -y --installroot=/mnt grouplist

the group files are located in /mnt/var/cache/yum/$reponame/*.xml for example installing everything (required disc space ~8G) can be achieve by calling

• $ yum -y --installroot=/mnt install \*

things you still need to adopt after successful installation for base functionality

• /etc/resolv.conf
• /etc/sysconfig/network-scripts/ifcfg-eth*
• umount /mnt/proc

• sync

• umount /mnt
• edit your domU Config File and start the domU