nixpkgs/modules/virtualisation/amazon-image.nix
2010-07-13 20:47:31 +00:00

118 lines
4 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 filesysten 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
# Amazon assumes that there is a /sbin/init, so create one.
# Note that simply creating /sbin/init as a symlink breaks
# some EC2 initrds (like Ubuntu's) because they do a "test
# -x $mountPoint/sbin/init".
mkdir -p /mnt/sbin
echo "#! /nix/var/nix/profiles/system/init" > /mnt/sbin/init
chmod +x /mnt/sbin/init
umount /mnt
''
);
# On EC2 we don't get to supply our own kernel, so we can't load any
# modules. However, dhclient fails if the ipv6 module isn't loaded,
# unless it's compiled without IPv6 support. So do that.
nixpkgs.config.packageOverrides = pkgsOld:
{ dhcp = pkgs.lib.overrideDerivation pkgsOld.dhcp (oldAttrs:
{ configureFlags = "--disable-dhcpv6";
});
};
fileSystems =
[ { mountPoint = "/";
device = "/dev/disk/by-label/nixos";
}
{ mountPoint = "/data";
device = "/dev/sda2";
autocreate = true;
}
];
swapDevices =
[ { device = "/dev/sda3"; } ];
# 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
echo "setting host name..."
${pkgs.nettools}/bin/hostname $(${pkgs.curl}/bin/curl http://169.254.169.254/1.0/meta-data/hostname)
'';
};
}