| Current File : //usr/local/jetapps/usr/share/rear/finalize/GNU/Linux/260_rename_diskbyid.sh |
# remove existing disk-by-id mappings
# FIXME: Don't we actually not 'remove' but 'replace' or 'migrate' disk-by-id mappings?
#
# We call sed once for each substitution
# it would be better to build one sed script and use this later
# (like finalize/GNU/Linux/250_migrate_disk_devices_layout.sh)
#
# OLD_ID_FILE contains entries like these (last 2 lines are multipath targets)
# dm-name-rootvg-lv_swap /dev/mapper/rootvg-lv_swap
# dm-name-rootvg-lvroot /dev/mapper/rootvg-lvroot
# dm-uuid-LVM-AkjnD2jS2SCCZKbxkZeaByuZLNdHc6qCYp35NGzNbhMaL3YZYtRxuPoerlAkOcj3 /dev/mapper/rootvg-lvroot
# dm-uuid-LVM-AkjnD2jS2SCCZKbxkZeaByuZLNdHc6qCeXNhvq6sxq6LQh4aksjr1WUANFuCKooc /dev/mapper/rootvg-lv_swap
# scsi-0QEMU_QEMU_CD-ROM_drive-scsi0-0-0-0 /dev/sr0
# virtio-a1bd20bf-f66d-442c-8 /dev/vda
# virtio-a1bd20bf-f66d-442c-8-part1 /dev/vda1
# virtio-a1bd20bf-f66d-442c-8-part2 /dev/vda2
# virtio-a1bd20bf-f66d-442c-8-part3 /dev/vda3
#
# cciss-3600508b100104c3953573830524b0004 /dev/cciss/c0d0
# cciss-3600508b100104c3953573830524b0004-part1 /dev/cciss/c0d0p1
FILES="/etc/fstab /boot/grub/menu.lst /boot/grub2/grub.cfg /boot/grub/device.map /boot/efi/*/*/grub.cfg /etc/lvm/lvm.conf /etc/lilo.conf /etc/yaboot.conf /etc/default/grub_installdevice"
OLD_ID_FILE="$VAR_DIR/recovery/diskbyid_mappings"
NEW_ID_FILE="$TMP_DIR/diskbyid_mappings"
[ ! -s "$OLD_ID_FILE" ] && return 0
[ -z "$FILES" ] && return 0
# Apply device mapping to replace device in case of migration.
# apply_layout_mappings() function defined in lib/layout-function.sh
# Inform the user when it failed to apply the layout mappings
# but do not error out here at this late state of "rear recover"
# regardless that when apply_layout_mappings failed
# some entries in OLD_ID_FILE got possibly corrupted,
# cf. https://github.com/rear/rear/issues/1845
# but hopefully the code below is sufficiently robust
# so that things work at least for those entries that are correct:
apply_layout_mappings "$OLD_ID_FILE" || LogPrintError "Failed to apply layout mappings to $OLD_ID_FILE (may cause failures during 'rename_diskbyid')"
# replace the device names with the real devices
while read ID DEV_NAME; do
ID_NEW=""
if [[ $DEV_NAME =~ ^dm- ]]; then
# probably a multipath device
# we cannot migrate device mapper targets
# we delete DEV_NAME to make sure it won't get used
DEV_NAME=""
else
# get symlinks defined by udev from a device
# UdevSymlinkName() defined in lib/layout-function.sh
SYMLINKS=$(UdevSymlinkName $DEV_NAME)
set -- $SYMLINKS
while [ $# -gt 0 ]; do
if [[ $1 =~ /dev/disk/by-id ]]; then
# bingo, we found what we are looking for
ID_NEW=${1#/dev/disk/by-id/} # cciss-3600508b1001cd2b56e1aeab1f82dd70d
break
else
shift
fi
done
fi
echo $ID $DEV_NAME $ID_NEW
done < "$OLD_ID_FILE" > "$NEW_ID_FILE"
sed_change_monitor="$TMP_DIR/by-id_change"
LogPrint "Migrating disk-by-id mappings in certain restored files in $TARGET_FS_ROOT to current disk-by-id mappings ..."
local file=""
local realfile=""
local symlink_target=""
for file in $FILES; do
realfile="$TARGET_FS_ROOT/$file"
# Silently skip directories and file not found:
test -f "$realfile" || continue
# 'sed -i' bails out on symlinks, so we follow the symlink and patch the symlink target
# on dead links we inform the user and skip them
# TODO: We should do this inside 'chroot $TARGET_FS_ROOT' so that absolute symlinks will work correctly
# cf. https://github.com/rear/rear/issues/1338
if test -L "$realfile" ; then
if symlink_target="$( readlink -f "$realfile" )" ; then
# symlink_target is an absolute path in the recovery system
# e.g. the symlink target of etc/mtab is /mnt/local/proc/12345/mounts
# because we use only 'pushd $TARGET_FS_ROOT' but not 'chroot $TARGET_FS_ROOT'.
# If the symlink target does not start with /mnt/local/ (i.e. if it does not start with $TARGET_FS_ROOT)
# it is an absolute symlink (e.g. inside $TARGET_FS_ROOT a symlink points to /absolute/path/file)
# and the target of an absolute symlink is not within the recreated system but in the recovery system
# where it does not make sense to patch files, cf. https://github.com/rear/rear/issues/1338
# so that we skip patching symlink targets that are not within the recreated system:
if ! echo $symlink_target | grep -q "^$TARGET_FS_ROOT/" ; then
LogPrint "Skip patching symlink $realfile target $symlink_target not within $TARGET_FS_ROOT"
continue
fi
# If the symlink target contains /proc/ /sys/ /dev/ or /run/ we skip it because then
# the symlink target is considered to not be a restored file that needs to be patched
# cf. https://github.com/rear/rear/pull/2047#issuecomment-464846777
if echo $symlink_target | grep -Eq '/proc/|/sys/|/dev/|/run/' ; then
LogPrint "Skip patching symlink $realfile target $symlink_target on /proc/ /sys/ /dev/ or /run/"
continue
fi
LogPrint "Patching symlink $realfile target $symlink_target"
realfile="$symlink_target"
else
LogPrint "Skip patching dead symlink $realfile"
continue
fi
fi
# keep backup
cp $v "$realfile" "$realfile.rearbak"
# we should consider creating a sed script within a string
# and then call sed once (as done other times)
while read ID DEV_NAME ID_NEW; do
if [ -n "$ID_NEW" ]; then
# If ID and ID_NEW are the same, no need to change, go the next device.
[[ "$ID" == "$ID_NEW" ]] && continue
# great, we found a new device
ID_FULL=/dev/disk/by-id/$ID
ID_NEW_FULL=/dev/disk/by-id/$ID_NEW
# Using w flag to store changes made by sed in a output file /dev/stdout
# then, we redirect output to $sed_change_monitor.
# if no change is made, $sed_change_monitor will stay empty.
sed -i "s#$ID_FULL\([^-a-zA-Z0-9]\)#$ID_NEW_FULL\1#gw /dev/stdout" "$realfile" >> "$sed_change_monitor"
# ^^^^^^^^^^^^^^^
# This is to make sure we get the full ID (and not
# a substring) because we ask sed for a char other then
# those contained in IDs.
# This does not work with IDs at line end: substitute also those:
sed -i "s#$ID_FULL\$#$ID_NEW_FULL#gw /dev/stdout" "$realfile" >> "$sed_change_monitor"
else
# lets try with the DEV_NAME as fallback
[ -z "$DEV_NAME" ] && continue
# not even DEV_NAME exists, we can't do anything
ID_FULL=$ID
sed -i "s#$ID_FULL\([^-a-zA-Z0-9]\)#/dev/$DEV_NAME\1#gw /dev/stdout" "$realfile" >> "$sed_change_monitor"
sed -i "s#$ID_FULL\$#/dev/$DEV_NAME#gw /dev/null" "$realfile" >> "$sed_change_monitor"
fi
# Checking if sed changed something in a file (by using w sed flag)
# LogPrint only when a change was made.
if test -s "$sed_change_monitor" ; then
LogPrint "Replaced '$ID_FULL' by '$ID_NEW_FULL' in $realfile"
rm "$sed_change_monitor"
fi
done < $NEW_ID_FILE
done
# TODO: Use 'local' variables for that:
unset ID DEV_NAME ID_NEW SYMLINKS ID_FULL ID_NEW_FULL