diskimage-builder/elements/dracut-ramdisk/post-install.d/99-build-dracut-ramdisk
Ben Nemec eed30adc48 Enable dracut deploy ramdisks
The element builds dracut from source on Ubuntu because the
Ubuntu dracut package is broken and very old, so it can't be
installed properly and causes a number of other issues that
are fixed by using a newer version of Dracut.

This initial version should work in virtualized environments.
Further validation of its suitability for real baremetal
deployments will need to be done in the future, but this should
be sufficient to enable that work.

Regarding Dracut specifically, in order to limit the changes
needed in the existing scripts this element continues to use a
cut down version of the /init script that we were building for the
existing ramdisk.  However, instead of running it as pid 0 it is
run as a Dracut pre-mount hook.  This allows Dracut to set up all
of the hardware and system bits, while falling early enough in the
Dracut sequence to complete the deployment before Dracut would try
to boot off the hard disk.

bp tripleo-juno-dracut-ramdisks
Change-Id: I144c8993fe040169f440bd4f7a428fdbe3d745cf
2014-10-17 21:44:09 -05:00

63 lines
2.4 KiB
Bash
Executable file

#!/bin/bash
set -eux
set -o pipefail
_LIB="/tmp/ramdisk-build"
source "$_LIB/common-defaults"
source "$_LIB/img-defaults"
source "$_LIB/ramdisk-defaults"
source "$_LIB/common-functions"
source "$_LIB/img-functions"
source "$_LIB/ramdisk-functions"
KERNEL_VERSION="${DIB_KERNEL_VERSION:-$(find_kernel_version)}"
MODULE_DIR="$MODULE_ROOT/lib/modules/$KERNEL_VERSION"
FIRMWARE_DIR="$MODULE_ROOT/lib/firmware"
LIB_UDEV="$LIB_UDEV_ROOT/lib/udev"
INIT="$_LIB/scripts/init"
FUNCTIONS_D="$_LIB/scripts/d"
MODULE="$_LIB/scripts/module"
# NOTE(bnemec): IMAGE_ELEMENT is normally set in disk-image-create, but we're
# not using that to build the image here.
IMAGE_ELEMENT=
mk_build_dir
mkdir -p "$TMP_BUILD_DIR/mnt"
export TMP_HOOKS_PATH=/tmp
export TMP_MOUNT_PATH="$TMP_BUILD_DIR/mnt"
echo "building ramdisk in $TMP_MOUNT_PATH"
populate_init
SCRIPT_HOME=/tmp/in_target.d/bin TMP_HOOKS_PATH=/tmp/in_target.d run_d ramdisk-install
MODULE_PATH="/usr/lib/dracut/modules.d"
cp -r "$MODULE" "$MODULE_PATH/80deploy-ramdisk"
cp "$TMP_MOUNT_PATH/init" "$MODULE_PATH/80deploy-ramdisk/init.sh"
# Notes on the options passed to Dracut:
# -N: Do not build a host-specific ramdisk. We want to be able to run this ramdisk
# on as many different machines as possible.
# --install: A list of the binaries needed by our ramdisk script fragments.
# --kernel-cmdline: Kernel parameters to pass to the ramdisk. rd.neednet is required
# to force Dracut to bring up networking even if it isn't passed a
# network target root. Pre-loading the ahci module is necessary
# on some systems to ensure that SATA disks are recognized.
# --include: Files from the chroot to include in the ramdisk.
# --kver: The kernel version to use, as determined above.
# --add-drivers: Extra kernel modules to include in the ramdisk.
# -o: Force omission of these dracut modules. Our scripts are written for bash,
# so dash is not desirable, and plymouth was causing some issues on Ubuntu.
dracut -N \
--install 'tail head awk ifconfig cut expr route ping tgtd tgtadm nc wget curl tftp grep' \
--kernel-cmdline "rd.shell rd.debug rd.neednet=1 rd.driver.pre=ahci" \
--include "$TMP_MOUNT_PATH/init-func" /init-func \
--kver "${KERNEL_VERSION}" \
--add-drivers "virtio virtio_net virtio_blk" \
-o "dash plymouth" \
/tmp/ramdisk
cp "/boot/vmlinuz-${KERNEL_VERSION}" /tmp/kernel
chmod o+r /tmp/kernel