Update / Create Lion RecoveryHD Partition Quickly Without Reinstalling

Apple released the Lion Recovery Update in October, 2011, and, after they updated the Lion recovery partition to 10.7.2, there was a great hint from Clay Caviness who dug into the update and highlighted the the relevant files and commands that it used to accomplish this update.

Recently, 10.7.3 came out, however, and the RecoveryHD partition is not updated if you use Software Update; it will stay at 10.7.2. This is probably not a big deal, as Apple didn’t deem it necessary to update, but for some users, this may not be good enough.

Note: Running the full 10.7.3 installer from the App Store will update the partition; this is fine for your home computer but not practical for large deployments.

Script Workflow:

  • Asks for locations of Recovery Update, Install OS X Lion.app, and destination
  • Expands and collects the dmtest tool from the Lion Recovery Update
  • Collects the hidden Basesystem chunklist and dmg found in the InstallESD.dmg inside “Install Mac OS X Lion.app”

The script making the Disk Image

  • Puts it all neatly into a self-contained disk image along with the script RecoveryHD Updater.command which can be used to easily create or update the RecoveryHD partition, even on the disk you are currently booted from; don’t worry dmtest takes care of all the logic to create or update.

The final disk image

Requirements:

  • Download the latest version of Install OS X Lion.app. Option-click the Purchases tab in the App Store and you will be able to “Install” (download) the latest version available
  • Download Lion Recovery Update from Apple

Script Tip:

Copy and paste the script into TextWrangler, save with a .command extension and it will automatically set the executable bit.

createRecoveryHDUpdater.command (downloadable script):

#!/bin/bash

#this script will make a disk image with the tools needed to update your Recovery HD with the newest OS X Lion release

#Required components:
#Lion Recovery Update v1.0 - http://support.apple.com/downloads/DL1464/en_US/RecoveryHDUpdate.dmg
#"Install Mac OS X Lion.app" - App Store

###########################
# RecoveryHD Updater.command
###########################

#this script that will be saved to the disk image that is created
RecoveryHDUpdaterScript='#!/bin/bash
clear;
MYPATH="$(dirname "$0")"

#get destination drive
if [ "$1" == "" ]; then
echo -n "Please drag in DESTINATION disk for Recovery HD partition and press Enter: "
while [ -z "$DEST" ]; do
read DEST
done
if [ ! -d "$DEST" ]; then echo "$DEST not found"; exit; fi
else
DEST="$1"
fi

#create Recovery partition
sudo "$MYPATH"/bin/dmtest ensureRecoveryPartition "$DEST" "$MYPATH"/etc/BaseSystem.dmg 0 0 "$MYPATH"/etc/BaseSystem.chunklist
'
######
# END
######

###########################
# VARIABLES
###########################

#IMAGETEMP is the pathname for the disk image being built, will the OS and Build appended to the name later
IMAGETEMP="/tmp/Recovery HD Updater"

#temp folder for package expansion
RECOVERY_EXPANDED="/tmp/RecoveryHDUpdate"

#Mounted disk image paths
ESDPATH="/Volumes/Mac OS X Install ESD"
RECOVERYPATH="/Volumes/Mac OS X Lion Recovery HD Update"

#############
# MAIN SCRIPT
#############
clear;
#get Recovery Update dmg path
if [ "$1" == "" ]; then
echo -n "Please drag in RecoveryHDUpdate.dmg and press enter: "
while [ -z "$RECOVERYHDUPDATE" ]; do
read RECOVERYHDUPDATE
done
if [ ! -f "$RECOVERYHDUPDATE" ]; then echo "$RECOVERYHDUPDATE not found"; exit; fi
else
RECOVERYHDUPDATE="$1"
fi

#get Lion Installer path
if [ "$2" == "" ]; then
echo -n "Please drag in \"Install Mac OS X Lion.app\" and press enter: "
while [ -z "$LION" ]; do
read LION
done
if [ ! -d "$LION" ]; then echo "$LION not found"; exit; fi
else
LION="$2"
fi

#get destination path for disk image to be created at
if [ "$3" == "" ]; then
echo -n "Please drag in Destination folder for disk image: "
while [ -z "$DEST" ]; do
read DEST
done
if [ ! -d "$DEST" ]; then echo "$DEST is not a valid path"; exit; fi
else
DEST="$3"
fi

#mount Recovery Update image
hdiutil attach "$RECOVERYHDUPDATE"

#expand packge inside to temp folder (contains dmtest)
pkgutil --expand "$RECOVERYPATH"/RecoveryHDUpdate.pkg "$RECOVERY_EXPANDED"

#if we were using what's inside the chunklist and recovery inside the update we would mount this
#RecoveryHDMeta="/Volumes/Recovery HD Update"
#hdiutil attach "$RECOVERY_EXPANDED"/RecoveryHDUpdate.pkg/RecoveryHDMeta.dmg

#open Lion install ESD image for the newest files
hdiutil attach "$LION"/Contents/SharedSupport/InstallESD.dmg

#get OS version from Lion Installer ESD
OSVER=$(defaults read "$ESDPATH"/System/Library/CoreServices/SystemVersion ProductUserVisibleVersion)
OSBUILD=$(defaults read "$ESDPATH"/System/Library/CoreServices/SystemVersion ProductBuildVersion)

#append info to path so disk image volume name is informative and useful
IMAGETEMP="$IMAGETEMP $OSVER $OSBUILD"

#make work the folder
mkdir -p "$IMAGETEMP"/etc/
mkdir "$IMAGETEMP"/bin/

#copy dmtest to IMAGETEMP
if [ -f "$RECOVERY_EXPANDED"/RecoveryHDUpdate.pkg/Scripts/Tools/dmtest ]; then
cp "$RECOVERY_EXPANDED"/RecoveryHDUpdate.pkg/Scripts/Tools/dmtest "$IMAGETEMP"/bin/
else
echo "$RECOVERY_EXPANDED/RecoveryHDUpdate.pkg/Scripts/Tools/dmtest not found, exiting"
exit 1
fi

#copy the BaseSystem dmg and chunklist to destination/etc
if [ -f "$ESDPATH"/BaseSystem.chunklist -o -f "$ESDPATH"/BaseSystem.dmg  ]; then
cp "$ESDPATH"/BaseSystem.chunklist "$ESDPATH"/BaseSystem.dmg "$IMAGETEMP"/etc/
#unhide BaseSystem
chflags -R nohidden "$IMAGETEMP"
else
echo "$ESDPATH/BaseSystem* not found, exiting"
fi

#put script in folder root
echo "$RecoveryHDUpdaterScript" > "$IMAGETEMP"/"RecoveryHD Updater.command"
#set permissions
chmod ugo+x "$IMAGETEMP"/"RecoveryHD Updater.command"

#create disk image from folder
hdiutil create -srcfolder "$IMAGETEMP" "$DEST"/RecoveryHDUpdater_$OSVER_$OSBUILD.dmg
if [ $? -eq 0 ]; then
echo "Success! Created: $DEST/RecoveryHDUpdater_$OSVER_$OSBUILD.dmg"
echo "Now opening "$DEST"/RecoveryHDUpdater_$OSVER_$OSBUILD.dmg"
hdiutil attach "$DEST"/RecoveryHDUpdater_$OSVER_$OSBUILD.dmg
else
echo "Disk Image failed"
fi

echo "Cleaning Up"
#delete temp folders
rm -rf "$IMAGETEMP" "$RECOVERY_EXPANDED"

#eject the volumes
hdiutil eject "$RECOVERYPATH"
hdiutil eject "$ESDPATH"

echo "Done."

exit

The script can also be run with command line arguments:

$ ./createRecoveryHDUpdater.command [Recovery Update DMG] [Install Lion App] [Destination for DMG]

As well as the script that is put in the created disk image:

$ ./RecoveryHD\ Updater.command [Destination]

Otherwise just double-click it in the Finder and it will ask you for the files and paths which you can just drag into the Terminal window and press Enter (don’t worry about the trailing spaces it adds)

When you run the script in the disk image you will be prompted for an admin password and away it goes, with all sorts of ugly output because it never thought a human would gaze upon it’s hidden ways…

dmtest updating the RecoveryHD partition

 

Update: Just tested with 10.7.4 and this script still works correctly, nothing has changed in the structure of the updated Install OS X Lion.app from the App store, note that the 10.7.4 installer is version 1.0.21 (10.7.2=1.0.13 and 10.7.3=1.0.16)

Update: Script will work on 10.8 without modification, however I have updated the script anyway to be a bit quieter when mounting the various DMGs, to accept tilde paths, accept the RecoveryHDUpdater as either a DMG or PKG, and changed prompt phrasing to include Mountain Lion.

2 thoughts on “Update / Create Lion RecoveryHD Partition Quickly Without Reinstalling

  1. So I have installed Lion 10.7.3 from the Mac App Store on my iMac and assume that the RecoveryHD partition has also been updated. My question is, do I have to install Lion Recovery Update 1.0 now or is this update included in the 10.7.3 Mac App Store update?

  2. No need for Lion Recovery Update 1.0, that was for users of 10.7.1 who updated to 10.7.2. If Software Update doesn’t say you need it, you don’t need it! :)

Comments are closed.