Creates a bootable ISO image from a macOS installer application. This image can then be used to install macOS on a physical or virtual machine.
If you have ever needed to install macOS on a new computer, you have probably discovered the ability to create a bootable USB flash drive or other volume by using the createinstallmedia command included in the downloaded macOS installer: Create a bootable installer.
In case you need a bootable ISO image instead, you can find a lot of shell scripts in forums that create such an ISO image for certain macOS versions. However, they are often only written for a single macOS version and cannot adapt to the specific macOS version contained in the installer.
The purpose of this program createinstalliso is to create a bootable ISO image from a downloaded full macOS installer. In addition, the program should:
- Automatically adapt the strategy used to create the ISO image to the installer application type, thereby supporting a wide range of macOS versions (see: Compatibility).
- Look and feel like Apple's
createinstallmediacommand (e.g. handling of command line arguments, wording for error and progress messages, status codes used when exiting). - Behaving like a standard command line program (e.g. Ctrl-C interruptibility, proper cleanup of resources before exiting), even though it is a Bash script.
To run createinstalliso you need:
- A machine running Mac OS X Snow Leopard 10.6 or later.
- An administrator user and password required for the use of the
sudocommand. - A downloaded full macOS installer for Mac OS X Lion 10.7 or later.
Note: Make sure that you have downloaded a full macOS installer which should have a size of at least 5 GB.
The table below shows:
- Whether a macOS version can run createinstalliso.
- Which macOS installers can be used to create an ISO image with this particular macOS version.
| macOS | Version | Can run createinstalliso | Can use installer for |
|---|---|---|---|
| Mac OS X Cheetah | 10.0 | No | N/A |
| Mac OS X Puma | 10.1 | No | N/A |
| Mac OS X Jaguar | 10.2 | No | N/A |
| Mac OS X Panther | 10.3 | No | N/A |
| Mac OS X Tiger | 10.4 | No | N/A |
| Mac OS X Leopard | 10.5 | No | N/A |
| Mac OS X Snow Leopard | 10.6 | Yes | 10.7 - 10.11 |
| Mac OS X Lion | 10.7 | Yes | 10.7 - 10.11 |
| OS X Mountain Lion | 10.8 | Yes | 10.7 - 10.15 |
| OS X Mavericks | 10.9 | Yes | 10.7 - 12 |
| OS X Yosemite | 10.10 | Yes | 10.7 - 12 |
| OS X El Capitan | 10.11 | Yes | 10.7 - 13 |
| macOS Sierra | 10.12 | Yes | 10.7 - 13 |
| macOS High Sierra | 10.13 | Yes | 10.7 - 15 |
| macOS Mojave | 10.14 | Yes | 10.7 - 15 |
| macOS Catalina | 10.15 | Yes | 10.7 - 15 |
| macOS Big Sur | 11 | Yes | 10.7 - 15 |
| macOS Monterey | 12 | Yes | 10.7 - 15 |
| macOS Ventura | 13 | Yes | 10.7 - 15 |
| macOS Sonoma | 14 | Yes | 10.7 - 15 |
| macOS Sequoia | 15 | Yes | 10.7 - 15 |
The table below shows:
- Which macOS version is required to use createinstalliso with a particular macOS installer.
| Installer for | Version | Required macOS version |
|---|---|---|
| Mac OS X Cheetah | 10.0 | N/A |
| Mac OS X Puma | 10.1 | N/A |
| Mac OS X Jaguar | 10.2 | N/A |
| Mac OS X Panther | 10.3 | N/A |
| Mac OS X Tiger | 10.4 | N/A |
| Mac OS X Leopard | 10.5 | N/A |
| Mac OS X Snow Leopard | 10.6 | N/A |
| Mac OS X Lion | 10.7 | 10.6 or later |
| OS X Mountain Lion | 10.8 | 10.6 or later |
| OS X Mavericks | 10.9 | 10.6 or later |
| OS X Yosemite | 10.10 | 10.6 or later |
| OS X El Capitan | 10.11 | 10.6 or later |
| macOS Sierra | 10.12 | 10.8 or later |
| macOS High Sierra | 10.13 | 10.8 or later |
| macOS Mojave | 10.14 | 10.8 or later |
| macOS Catalina | 10.15 | 10.8 or later |
| macOS Big Sur | 11 | 10.9 or later |
| macOS Monterey | 12 | 10.9 or later |
| macOS Ventura | 13 | 10.11 or later |
| macOS Sonoma | 14 | 10.13 or later |
| macOS Sequoia | 15 | 10.13 or later |
Open Terminal, which is in the Utilities folder of your Applications folder, and type or paste the following commands into Terminal:
-
Download the createinstalliso file.
curl -fOSs https://raw.githubusercontent.com/BITespresso/createinstalliso/master/createinstalliso -
Make the downloaded script executable.
chmod +x createinstalliso -
A good practice is to keep your shell scripts in the
binfolder in your home directory. If it does not already exist, create it and move the script to this folder.mkdir -p ~/bin mv createinstalliso ~/bin/ -
You might also want to hide the
binfolder from the Finder.chflags hidden ~/bin
Note: Of course you can also choose a different folder such as /usr/local/bin to save the script.
Just like Apple's createinstallmedia command createinstalliso must be run as root user. Depending on where you saved the script, the command will look like:
sudo ~/bin/createinstalliso --isodirectory <path to ISO directory> --applicationpath <path to OS installer application> [--nointeraction]
The command createinstalliso requires the following two command line arguments:
--isodirectory(or-i) must be followed by a path to a directory where the installer ISO image file will be created.--applicationpath(or-a) must be followed by a path to a copy of the OS installer application to create the bootable ISO image from.
The name of the ISO image to be created is made up of the name of the installer and has the extension iso (e.g. Install macOS Catalina.iso). If such a file already exists in the specified destination directory, you will be prompted for confirmation before this file is overwritten. If you do not care about overwriting an existing file and do not want to be prompted, you can add the command line option --nointeraction.
If you want to suppress user interactions when running the command and always allow the required actions, you can add the option:
--nointeraction(or-n) causes an existing ISO image file to always be overwritten.
The following example show the steps required to create an ISO image from a macOS Catalina installer:
-
Open Terminal, which is in the Utilities folder of your Applications folder.
-
Type or paste the following command into Terminal, then press Return to enter the command. This assumes that the installer is still in your Applications folder, and you have moved createinstalliso to the
~/binfolder.sudo ~/bin/createinstalliso --isodirectory ~/Desktop/ --applicationpath /Applications/Install\ macOS\ Catalina.app/ -
When prompted, type your administrator password. Terminal doesn't show any characters as you type. Then press Return.
-
Terminal shows the progress as the bootable ISO image is created.
-
When Terminal says that it's done, you will find the bootable ISO image
Install macOS Catalina.isoin the folder you specified (here:~/Desktop). -
You can now quit Terminal.
If you try to install macOS using the ISO image you created, you may see an alert that says the application can't be verified and may have been corrupted or tampered with during downloading. Or it says that the package was signed with a certificate that has expired and may not be authentic (see: If an installer says it can't be verified or was signed with a certificate that has expired).
The most likely reason for this message is that the installer was signed with a certificate that expired on October 24, 2019. You must therefore either get a new installer signed with a currently valid certificate or temporarily set the system date to a date in the past when the certificate was still valid.
To manually set the system date to a value in the past, perform the following steps after the above warning is displayed during the macOS installation:
- Close the alert.
- Open Terminal from the Utilities menu.
- Type
date 100800002019into Terminal, then press Return. This sets the system date to October 8, 2019, 0:00 am. - Quit Terminal and resume the macOS installation.
Apple has used different internal structures for its macOS installers over time. Therefore, createinstalliso examines the internal structure of the installer and determines which 'type' it is. Based on this 'type', the necessary steps to create a bootable ISO image are performed.
The installer application types are:
| Name | Version | Type |
|---|---|---|
| Mac OS X Lion | 10.7 | 1 |
| OS X Mountain Lion | 10.8 | 1 |
| OS X Mavericks | 10.9 | 2 |
| OS X Yosemite | 10.10 | 2 |
| OS X El Capitan | 10.11 | 2 |
| macOS Sierra | 10.12 | 3 |
| macOS High Sierra | 10.13 | 3 |
| macOS Mojave | 10.14 | 3 |
| macOS Catalina | 10.15 | 3 |
| macOS Big Sur | 11 | 4 |
| macOS Monterey | 12 | 4 |
| macOS Ventura | 13 | 4 |
| macOS Sonoma | 14 | 4 |
| macOS Sequoia | 15 | 4 |
createinstalliso uses a number of external commands, which must be available on your system:
awkblesscodesigncpcutdfdittodufilegrephdiutilmktemppspwdrmrsyncscriptseqstatsw_verssysctltputunamexattr/usr/libexec/PlistBuddy.
Unless you have deliberately modified your system, all of the above commands are available on the macOS versions listed in the section "Compatibility".
A failure of createinstalliso is indicated by a non-zero exit status. Wherever possible, createinstalliso uses an exit status and and exit message identical to createinstallmedia.
The table below lists all possible exit status and corresponding messages:
| Status | Message |
|---|---|
| 255 | You must specify both the ISO directory and install application path. |
| 255 | createinstalliso: unrecognized option `[OPTION]' |
| 255 | createinstalliso: invalid option -- [OPTION] |
| 255 | createinstalliso: option `[OPTION]' requires an argument |
| 255 | createinstalliso: option requires an argument -- [OPTION] |
| 255 | createinstalliso: option `[OPTION]' doesn't allow an argument |
| 255 | createinstalliso: option `[OPTION]' is ambiguous |
| 254 | [DIRECTORY] is not a valid ISO directory. |
| 253 | [FILE] does not appear to be a valid OS installer application. |
| 252 | This tool must be run in Bash shell. |
| 251 | Couldn't get operating system name. |
| 250 | This tool must be run on macOS. |
| 249 | This tool must be run as root. |
| 248 | Couldn't get macOS version. |
| 247 | Invalid macOS version. |
| 246 | [VOLUME] is not large enough for [FILE(S)]. An additional [SIZE] is needed. |
| 245 | This tool requires [VERSION] or later. |
| 244 | Couldn't get absolute path for [FILE]. |
| 243 | Couldn't get absolute path for [DIRECTORY]. |
| 242 | Couldn't get installer application display name. |
| 241 | Couldn't get installer application type. |
| 240 | Failed to create temporary directory. |
| 239 | Couldn't get device ID. |
| 238 | You need [VERSION] or later to create an ISO image from this installer application. |
| 237 | Failed to delete the [FILETYPE] [FILE]. |
| 236 | Mount of outer dmg failed. |
| 235 | BaseSystem missing from the outer dmg, damaged installer image? |
| 234 | Failed to convert BaseSystem.dmg. |
| 233 | Failed to resize disk image. |
| 232 | The disk image did not mount. |
| 231 | Failed to delete Packages symlink. |
| 230 | Failed to copy Packages directory. |
| 229 | The bless of the installer disk image failed. |
| 228 | Failed to copy BaseSystem.dmg. |
| 227 | Failed to copy BaseSystem.chunklist. |
| 226 | Couldn't unmount disk image. |
| 225 | Failed to create disk image. |
| 224 | Failed to convert disk image into bootable install media. |
| 223 | Failed to create ISO image. |
| 222 | [NOT USED SINCE 1.1] |
| 221 | Couldn't get installer application minimum macOS version. |
| 220 | Failed to copy installer application. |
| 219 | Failed to remove extended attribute com.apple.quarantine. |
| 218 | Failed to patch macOS Sierra installer application. |
| 217 | Failed to replace code signatures. |
| 216 | Failed to replace modified files with original ones. |
Copyright (C) 2021-2024 Michael Berger (BITespresso)
createinstalliso is licensed under the GNU General Public License v3 (GPL-3) (http://www.gnu.org/copyleft/gpl.html).