#!/bin/bash
# 
# $Header$
# 
# Build and copy pristine root filesystem to host roots for Xen
# 
# Copyright (C) 2005  Christopher G. Stach II <cgs@ldsys.net>
# 
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
# 

# Here's the diff to set up a single xenU guest -cgs

# diff -ur /etc/xen/xmexample1 /etc/xen/auto/db1.foo.domain.tld
# --- /etc/xen/xmexample1 2005-05-31 16:42:31.000000000 -0500
# +++ /etc/xen/auto/db1.foo.domain.tld    2005-06-02 16:53:56.000000000 -0500
# @@ -8,7 +8,7 @@
# 
#  #----------------------------------------------------------------------------
#  # Kernel image file.
# -kernel = "/boot/vmlinuz-2.6.10-xenU"
# +kernel = "/boot/vmlinuz-2.6.11.10-xenU"
# 
#  # Optional ramdisk.
#  #ramdisk = "/boot/initrd.gz"
# @@ -20,7 +20,7 @@
#  memory = 64
# 
#  # A name for your domain. All domains must have different names.
# -name = "ExampleDomain"
# +name = "db1.foo.domain.tld"
# 
#  # Which CPU to start domain on?
#  #cpu = -1   # leave to Xen to pick
# @@ -34,6 +34,7 @@
#  # Optionally define mac and/or bridge for the network interfaces.
#  # Random MACs are assigned if not given.
#  #vif = [ 'mac=aa:00:00:00:00:11, bridge=xen-br0' ]
# +vif = [ 'mac=de:ad:c0:ff:ee:01' ]
# 
#  #----------------------------------------------------------------------------
#  # Define the disk devices you want the domain to have access to, and
# @@ -42,7 +43,7 @@
#  # where UNAME is the device, DEV is the device name the domain will see,
#  # and MODE is r for read-only, w for read-write.
# 
# -disk = [ 'phy:hda1,hda1,w' ]
# +disk = [ 'phy:vg0/db1-root,sda1,w', 'phy:vg0/db1-swap,sda2,w', 'phy:vg0/db1-share,sda3,w' ]
# 
#  #----------------------------------------------------------------------------
#  # Set the kernel command line for the new domain.
# @@ -61,7 +62,7 @@
#  #hostname= "vm%d" % vmid
# 
#  # Set root device.
# -root = "/dev/hda1 ro"
# +root = "/dev/sda1 ro"
# 
#  # Root device for nfs.
#  #root = "/dev/nfs"
# @@ -71,7 +72,7 @@
#  #nfs_root   = '/full/path/to/root/directory'
# 
#  # Sets runlevel 4.
# -extra = "4"
# +#extra = "4"
# 
#  #----------------------------------------------------------------------------
#  # Set according to whether you want the domain restarted when it exits.

# All of the hosts we'll configure -cgs
readonly HOSTS="db1 ldap1 nms1 ns1 rsync1 www1"

# Hosts that need some dedicated partitions -cgs
readonly SHARE_HOSTS="db1 srv1"

# These hosts belong to this domain -cgs
readonly DOMAIN="foo.domain.tld"

# This can be an entire disk, also.  If it is, don't use grub on it! -cgs
readonly LVM_DEV="/dev/hdb1"

readonly VOLGROUP="vg0"

readonly NEW_ROOT="/mnt/new"

readonly PRISTINE_ROOT="/mnt/pristine"

readonly PRISTINE_NAME="pristine-`/bin/date +'%Y%m%d'`-root"

#
# Pick a mirror.  This is the one I used. -cgs
# 
# NO TRAILING SLASH! -cgs
#
readonly STAGE1PATH="http://gentoo.chem.wisc.edu/gentoo/releases/x86/2005.0/stages/x86"

readonly STAGE1FILE="stage1-x86-2005.0.tar.bz2"

function build_lv() {
	echo "Building LV ${2} / '${1}'..."
	/sbin/lvcreate -L${2} -n ${1} ${VOLGROUP}
	/sbin/mke2fs -v -M / -L / -j /dev/${VOLGROUP}/${1}
}

function build_lv_swap() {
	echo "Building LV ${2} swap '${1}'..."
	/sbin/lvcreate -L${2} -n ${1} ${VOLGROUP}
	/sbin/mkswap -c /dev/${VOLGROUP}/${1}
}

function build_lv_share() {
	echo "Building LV ${2} /mnt/share '${1}'..."
	/sbin/lvcreate -L${2} -n ${1} ${VOLGROUP}
	/sbin/mke2fs -v -M /mnt/share -L /mnt/share -j /dev/${VOLGROUP}/${1}
}

/sbin/pvcreate -M2 ${LVM_DEV}

/sbin/vgcreate ${VOLGROUP} ${LVM_DEV}

build_lv ${PRISTINE_NAME} 4G

/bin/mkdir -p ${PRISTINE_ROOT}

/bin/mount -t ext3 /dev/${VOLGROUP}/${PRISTINE_NAME} ${PRISTINE_ROOT}

/usr/bin/wget "${STAGE1PATH}/${STAGE1FILE}"

/usr/bin/wget "${STAGE1PATH}/${STAGE1FILE}.md5"

/usr/bin/md5sum -c "${STAGE1FILE}.md5" > /dev/null 2>&1

if [ $? -ne 0 ]; then
	echo "error: Stage 1 checksum failed"
	exit 1
fi

/bin/cat ${STAGE1FILE} | ( cd ${PRISTINE_ROOT} ; tar jxvpf - )

# Unpack stage1 into ${PRISTINE_ROOT} (done above), chroot, bootstrap,
# emerge -e system, etc.  Perform the usual steps, but keep the installation
# trimmed down.  Configure fstab for the root and swap partitions.  Then:
# 
# rc-update del consolefont boot
# rc-update del hdparm boot
# rc-update del hotplug default
# rc-update del keymaps default
# 
# Also, make sure that ntp-client and ntpd aren't in any runlevels.
# -cgs
# 

/bin/rm -f ${PRISTINE_ROOT}/etc/localtime

/bin/ln -s ../usr/share/zoneinfo/US/Central ${PRISTINE_ROOT}/etc/localtime

echo "${DOMAIN}" > ${PRISTINE_ROOT}/etc/dnsdomainname

# Maybe do this in the host loop if you want mail to look like it comes from
# the specific host
# -cgs
/bin/sed "s/rewriteDomain=/rewriteDomain=${DOMAIN}/" \
	< ${PRISTINE_ROOT}/etc/ssmtp/ssmtp.conf \
	> /tmp/ssmtp.$$

/bin/mv -f /tmp/ssmtp.$$ ${PRISTINE_ROOT}/etc/ssmtp/ssmtp.conf

echo "SYNC=\"rsync://rsync.${DOMAIN}/gentoo-portage\"" >> ${PRISTINE_ROOT}/etc/make.conf

/bin/mkdir -p ${NEW_ROOT}

for host in ${HOSTS}; do
	/bin/echo -n "Configuring root for '${host}'... "

	build_lv ${host}-root 4G

	build_lv_swap ${host}-swap 256M

	/bin/mount -t ext3 /dev/${VOLGROUP}/${host}-root ${NEW_ROOT}

	( \
		cd ${PRISTINE_ROOT} ; \
		/usr/bin/find . \! -path ./lost+found -depth \
			| cpio -pdmv ${NEW_ROOT} \
	)

	echo "${host}" > ${NEW_ROOT}/etc/hostname

	/bin/umount ${NEW_ROOT}

	echo "Done!"
done

for host in ${SHARE_HOSTS}; do
	build_lv_share ${host}-share 4G

	/bin/mount -t ext3 /dev/${VOLGROUP}/${host}-root ${NEW_ROOT}

	/bin/mkdir -p ${NEW_ROOT}/mnt/share

	/bin/umount ${NEW_ROOT}

	/bin/mount -t ext3 /dev/${VOLGROUP}/${host}-share ${NEW_ROOT}

	# In the guests, I use sda1 for / and sda2 for swap.  sda3 is the
	# next logical choice.
	# -cgs
	echo "/dev/sda3 /mnt/share ext3 defaults 0 2" >> ${NEW_ROOT}/etc/fstab

	/bin/umount ${NEW_ROOT}
done

exit 0