Bare Minimum to boot Stage3 gentoo @ ec2

gentoo-ec2.sh

#!/bin/sh
# -*- sh -*-

# NOTE: This is the bare min needed to make an ec2 image from a stage3 gentoo image.

# !st Build a stage3 from somewhere.  I use metro.  ...then... ->

#
# Configure
#

# Bootstrap for EC2 (TODO Most of this below needs to be added to metro)
mkdir -p /mnt/gentoo
tar xjof /home/mirror/linux/gentoo/$TYPE/stage3-$TYPE-current.tar.bz2 \
  -C /mnt/gentoo
mkdir -p /mnt/gentoo/lib/modules
cp /etc/resolv.conf /mnt/gentoo/etc
mount -t proc none /mnt/gentoo/proc
mount -o bind /dev /mnt/gentoo/dev
chroot /mnt/gentoo /bin/bash
env-update
source /etc/profile

etc-update ; # FIXME Metro left behind crufty locale.gen file !?!
emerge --sync

# rc
emerge dhcpcd
rc-update add net.eth0 default
rc-update add sshd default

# /etc/fstab
cat >/etc/fstab <<\EOF
# /etc/fstab: static file system information.
#
# noatime turns off atimes for increased performance (atimes normally aren't
# needed; notail increases performance of ReiserFS (at the expense of storage
# efficiency).  It's safe to drop the noatime options if you want and to
# switch between notail / tail freely.
#
# The root filesystem should have a pass number of either 0 or 1.
# All other filesystems should have a pass number of 0 or greater than 1.
#
# See the manpage fstab(5) for more information.
#

# <fs>			<mountpoint>	<type>		<opts>		<dump/pass>

# NOTE: If your BOOT partition is ReiserFS, add the notail option to opts.
### vvv ###
/dev/sda1 /        ext3  user_xattr,noatime  0 1
/dev/sda2 /mnt     ext3  user_xattr,noatime  0 2
/dev/sda3 swap     swap  sw                  0 0
### ^^^ ###

# glibc 2.2 and above expects tmpfs to be mounted at /dev/shm for
# POSIX shared memory (shm_open, shm_unlink).
# (tmpfs is a dynamically expandable/shrinkable ramdisk, and will
#  use almost no memory if not populated with files)
shm			/dev/shm	tmpfs		nodev,nosuid,noexec	0 0
EOF

# boothook
cat >/etc/conf.d/local.start <<EOF
# /etc/conf.d/local.start

# This is a good place to load any misc programs
# on startup (use &>/dev/null to hide output)

### vvv ###
mkdir -p /root/.ssh 2>/dev/null
wget -O - http://169.254.169.254/2008-02-01/meta-data/public-keys/0/openssh-key\
  >/root/.ssh/authorized_keys
chmod -R go-rwsx /root
wget -O - http://169.254.169.254/2008-02-01/user-data | sh
### ^^^ ###
EOF

# done
exit
for i in {1..3}
do
   umount /mnt/gentoo/{dev,proc} ; sleep 1
done

#
# Image
#

# keys
mkdir -p /etc/ssl/ec2
cat >/etc/ssl/ec2/key.pem <<\THEEND
-----BEGIN PRIVATE KEY-----
<your ec2 priv key>
-----END PRIVATE KEY-----
THEEND
cat >/etc/ssl/ec2/crt.pem <<\THEEND
-----BEGIN CERTIFICATE-----
<your ec2 cert>
-----END CERTIFICATE-----
THEEND
chmod -R go-rwsx /etc/ssl/ec2

# bundle
modprobe loop
umount /mnt/im*
rm -rf /mnt/im*
rm -rf /mnt/gentoo/usr/portage ; # dont need this
rm -rf /mnt/gentoo/tmp /mnt/gentoo/var/tmp/*
rm /mnt/gentoo/etc/resolv.conf
rm /mnt/gentoo/root/.bash_history

if [ "$(uname -m)" == 'i686' ]; then
  export ARCH="i386"
else
  export ARCH="x86_64"
fi
export KERNEL=$(\
wget -q -O - http://169.254.169.254/2008-02-01/meta-data/kernel-id\
)
ec2-bundle-vol -u <your ec2 owner id> \
    -k /etc/ssl/ec2/key.pem -c /etc/ssl/ec2/crt.pem \
    --no-inherit -r $ARCH --kernel $KERNEL -d /mnt \
    -v /mnt/gentoo/ --fstab /mnt/gentoo/etc/fstab
export BUNDLE=gentoo-$(\
wget -q -O - http://169.254.169.254/2008-02-01/meta-data/instance-type\
)-$(date +%Y%m%d)
echo $BUNDLE
# NOW: Create an S3 bucket w/ $BUNDLE as the name
ec2-upload-bundle \
    -a <your ec2 access key> -s <your ec2 private access key> \
    --retry --batch -b $BUNDLE -m /mnt/image.manifest.xml
ec2-register \
    -K /etc/ssl/ec2/key.pem -C /etc/ssl/ec2/crt.pem \
    $BUNDLE/image.manifest.xml
# Optional - make it available to everyone
ec2-modify-image-attribute \
  -K /etc/ssl/ec2/key.pem -C /etc/ssl/ec2/crt.pem \
  -l -a all \
  <ami-id>