nixpkgs/modules/virtualisation/amazon-image.nix
Eelco Dolstra d550cc6d63 * Grmbl. Create the missing mount points.
svn path=/nixos/trunk/; revision=23592
2010-09-01 11:00:35 +00:00

144 lines
4.9 KiB
Nix

{ config, pkgs, ... }:
with pkgs.lib;
{
system.build.amazonImage =
pkgs.vmTools.runInLinuxVM (
pkgs.runCommand "amazon-image"
{ preVM =
''
mkdir $out
diskImage=$out/nixos.img
${pkgs.vmTools.kvm}/bin/qemu-img create -f raw $diskImage "4G"
'';
buildInputs = [ pkgs.utillinux pkgs.perl ];
exportReferencesGraph =
[ "closure" config.system.build.toplevel ];
}
''
# Create an empty filesystem and mount it.
${pkgs.e2fsprogs}/sbin/mkfs.ext3 -L nixos /dev/vda
${pkgs.e2fsprogs}/sbin/tune2fs -c 0 -i 0 /dev/vda
mkdir /mnt
mount /dev/vda /mnt
# The initrd expects these directories to exist.
mkdir /mnt/dev /mnt/proc /mnt/sys
# Copy all paths in the closure to the filesystem.
storePaths=$(perl ${pkgs.pathsFromGraph} $ORIG_TMPDIR/closure)
mkdir -p /mnt/nix/store
cp -prvd $storePaths /mnt/nix/store/
# Register the paths in the Nix database.
printRegistration=1 perl ${pkgs.pathsFromGraph} $ORIG_TMPDIR/closure | \
chroot /mnt ${config.environment.nix}/bin/nix-store --load-db
# Create the system profile to allow nixos-rebuild to work.
chroot /mnt ${config.environment.nix}/bin/nix-env \
-p /nix/var/nix/profiles/system --set ${config.system.build.toplevel}
# `nixos-rebuild' requires an /etc/NIXOS.
mkdir -p /mnt/etc
touch /mnt/etc/NIXOS
# Install a configuration.nix.
mkdir -p /mnt/etc/nixos
cp ${./amazon-config.nix} /mnt/etc/nixos/configuration.nix
# Generate the GRUB menu.
chroot /mnt ${config.system.build.toplevel}/bin/switch-to-configuration boot
umount /mnt
''
);
fileSystems =
[ { mountPoint = "/";
device = "/dev/disk/by-label/nixos";
}
{ mountPoint = "/ephemeral0";
device = "/dev/xvdc";
neededForBoot = true;
}
];
swapDevices =
[ { device = "/dev/xvdb"; } ];
boot.initrd.kernelModules = [ "xen-blkfront" "aufs" ];
boot.kernelModules = [ "xen-netfront" ];
boot.extraModulePackages = [ config.boot.kernelPackages.aufs2 ];
# Generate a GRUB menu. Amazon's pv-grub uses this to boot our kernel/initrd.
boot.loader.grub.device = "nodev";
boot.loader.grub.timeout = 0;
boot.loader.grub.extraPerEntryConfig = "root (hd0)";
# Put /tmp and /var on /ephemeral0, which has a lot more space.
# Unfortunately we can't do this with the `fileSystems' option
# because it has no support for creating the source of a bind
# mount. Also, "move" /nix to /ephemeral0 by layering an AUFS
# on top of it so we have a lot more space for Nix operations.
boot.initrd.postMountCommands =
''
mkdir -m 1777 -p $targetRoot/ephemeral0/tmp
mkdir -m 1777 -p $targetRoot/tmp
mount --bind $targetRoot/ephemeral0/tmp $targetRoot/tmp
mkdir -m 755 -p $targetRoot/ephemeral0/var
mkdir -m 755 -p $targetRoot/var
mount --bind $targetRoot/ephemeral0/var $targetRoot/var
mkdir -m 755 -p $targetRoot/ephemeral0/nix
mount -t aufs -o dirs=$targetRoot/ephemeral0/nix=rw:$targetRoot/nix=rr none $targetRoot/nix
'';
# There are no virtual consoles.
services.mingetty.ttys = [ ];
# Allow root logins only using the SSH key that the user specified
# at instance creation time.
services.openssh.enable = true;
services.openssh.permitRootLogin = "without-password";
# Obtain the SSH key and host name at startup time.
jobs.fetchEC2Data =
{ name = "fetch-ec2-data";
startOn = "ip-up";
task = true;
script =
''
echo "obtaining SSH key..."
mkdir -p /root/.ssh
${pkgs.curl}/bin/curl --retry 3 --retry-delay 0 --fail \
-o /root/key.pub \
http://169.254.169.254/1.0/meta-data/public-keys/0/openssh-key
if [ $? -eq 0 -a -e /root/key.pub ]; then
if ! grep -q -f /root/key.pub /root/.ssh/authorized_keys; then
cat /root/key.pub >> /root/.ssh/authorized_keys
echo "new key added to authorized_keys"
fi
chmod 600 /root/.ssh/authorized_keys
rm -f /root/key.pub
fi
# Print the host public key on the console so that the user
# can obtain it securely by parsing the output of
# ec2-get-console-output.
echo "-----BEGIN SSH HOST KEY FINGERPRINTS-----" > /dev/console
${pkgs.openssh}/bin/ssh-keygen -l -f /etc/ssh/ssh_host_dsa_key.pub > /dev/console
echo "-----END SSH HOST KEY FINGERPRINTS-----" > /dev/console
echo "setting host name..."
${pkgs.nettools}/bin/hostname $(${pkgs.curl}/bin/curl http://169.254.169.254/1.0/meta-data/hostname)
'';
};
}