# To get a package list without version numbers from a target system
# rpm -qa --qf "%{n} " > packages.txt
# Put contents of packages.txt after "-y install \" line below

installroot="/ostemplate"
mount="$(mktemp -d --tmpdir)"
tmpyumconf=$mount/yum.conf

cat > $tmpyumconf << __YUMCONF__
[centos7]
name=centos 7 x86_64
baseurl=http://buildlogs.centos.org/centos/7/os/x86_64-20140617/
enabled=1
gpgcheck=0
__YUMCONF__

# Install the Core group
yum \
--installroot $installroot \
-c $tmpyumconf \
-y groupinstall \
  Core

# Install the necessary rpms
yum \
--installroot $installroot \
-c $tmpyumconf \
-y install \
  openssh-clients \
  openssh-server \
  yum \
  yum-utils \
  man \
  wget \
  sudo \
  tar \
  passwd

# Remove firmware files if installed
yum \
--installroot $installroot \
-c $tmpyumconf \
-y remove \
  aic94xx-firmware \
  alsa-firmware \
  alsa-tools-firmware \
  efibootmgr \
  ethtool \
  ivtv-firmware \
  iwl100-firmware \
  iwl105-firmware \
  iwl135-firmware \
  iwl1000-firmware \
  iwl2000-firmware \
  iwl2030-firmware \
  iwl3160-firmware \
  iwl3945-firmware \
  iwl4965-firmware \
  iwl5000-firmware \
  iwl5150-firmware \
  iwl6000-firmware \
  iwl6000g2a-firmware \
  iwl6000g2b-firmware \
  iwl6050-firmware \
  iwl7260-firmware \
  kbd \
  libertas-sd8686-firmware \
  libertas-sd8787-firmware \
  libertas-usb8388-firmware \
  libertas-usb8388-olpc-firmware \
  linux-firmware \
  postfix \
  policycoreutils \
  selinux-policy \
  selinux-policy-targeted \
  sudo \
  upstart \
  xorg-x11-drv-ati-firmware \
  zd1211-firmware

# Clean the yum configuration
yum --installroot $installroot -c $tmpyumconf clean all

# Remove unnessary files from the build, that are not required on a VZ container
yum \
--installroot $installroot \
-c $tmpyumconf \
-y remove \
  grub2 \
  grub2-tools \
  grubby \
  centos-logos \
  plymouth \
  plymouth-scripts \
  kernel

# Remove /boot, as that is not required
chroot $installroot rm -rf /boot

# Create fstab file, which is required for VZ installtions
cat > $installroot/etc/fstab << __FSTAB__
none /dev/pts devpts rw,gid=5,mode=620 0 0
none /dev/shm tmpfs defaults 0 0
__FSTAB__

# GMT to be default, but change for requirement
chroot $installroot ln -sf /usr/share/zoneinfo/GMT /etc/localtime

# Misc post stuff for VZ
ln -s /proc/mounts $installroot/etc/mtab
rm -f $installroot/dev/null
mknod -m 600 $installroot/dev/console c 5 1

# Copy the yum config to the system
cp $tmpyumconf $installroot/etc/yum.repos.d/centos.repo

# Now compress the image
cd $installroot; tar -cpzf /root/centos-7-x86_64-viayum.tar.gz . ; cd
ls -lh /root/centos-7-x86_64-viayum.tar.gz