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FlyingToasterStrudel

macrumors newbie
Original poster
Oct 26, 2021
24
25
Hello.

I’m very adept at using the createinstallmedia command-line tool to make bootable installer drives on USB thumb drives. I’m about to embark on a project that will require me to update macOS on a bunch of somewhat older Intel Macs (approx. 2010 to 2020 era). For the sake of making more efficient use of the USB thumb drives I have on-hand, I want to take just one of my 64 GB drives and place five macOS installer drive volumes on it…
  • High Sierra (8 GB)
  • Mojave (8 GB)
  • Catalina (16 GB)
  • Big Sur (16 GB)
  • Monterey (16 GB)
(Possibly will be Mojave-thru-Ventura instead…)

I want to make sure this drive is readable and bootable on as wide a variety of Macs as possible.

My approach is going to be: to use Disk Utility to simply make five GPT partitions, with approximately the above-listed sizes.

But: I wanted to check with the forum first, to see if there is any advantage at all to using a different approach, eg. Core Storage logical volume groups or something? Is that even possible? Would I gain more flexibility down the road with such a strategy? Thanks.
 
GPT partition scheme with HFS+ partitions is the way to go.

You can try making one partition at a time. Use createinstallmedia. Then create the next partitition by splitting the one you just created, shrinking the old partition to the smallest possible size so that the new partition is as large as possible. Repeat until all the installers have been created.

Catalina might fit with 9 GB.
Big Sur, Monterey, and Ventura might fit with 14 GB.
Sonoma might fit with 15 GB.

If Disk Utility.app doesn't let you shrink the partitions, then use iPartition.app instead.
https://coriolis-systems.com
 
I have made dozens of installer drives, and have been making multiple installer drives since Lion appeared.
I have a few with everything from Leopard to Sonoma on one drive. (It's a hobby...:cool: )
All use standard GPT with HFS+ partitions.
I think this will be changing soon, as there is a limit on one device of 16 HFS partitions.
but, I have recently been making what I call "modern macOS": High Sierra to Sonoma
Those are the ones that are most useful now.

I used to carefully craft the size of each individual installer partition, so there was only about 60MB of free space on each volume. I can get all installers from Leopard to Mojave, 10 partitions bootable, on one 64GB flash drive.
Can't do that with the "modern" systems -- but, then I also do this on NVME drives, with a 500GB often less than $40, no need for best quality/speed for this use, and much faster file transfer speeds (compared to thumb drives)
 
Dayo automated this
That script is actually for creating a bootable uni-installer disk each time. Something like the instructions by @joevt is needed to create a bootable multi-installer disk but AFAIK, createinstallmedia can't be used for the older Mac OS.
 
For some macOS versions it is not as easy as just restore it to a partition. There is this issue with the expired certificate. The common error message is that the installer disk is invalid. Setting back the date to 2016 does not work on every installer. Some files manipulations are required.
 
createinstallmedia exists since Mac OS X 10.9 Mavericks.
I see. Apple seemed to *imply* it was El Capitan here https://support.apple.com/101578 although I note they did not actually state so. I expect it was introduced with the "*.app" installers which I know Yosemite has and possibly Mavericks.

One negative about simply running createinstallmedia is that the resulting bootable disk can only be used on units that support that Mac OS version. So, you cannot create a Catalina installer with createinstallmedia and run this on cMP.

The Install_USB_Maker script reconstitutes the installers after stripping the supported unit and other requirements such as certs out before creating the bootable disk (Legacy *.dmg Installers ... Lion to LoSierra) or dumping the ISO for burning (Modern *.app Installers ... Yosemite to Monterey). Such can then be used for installation via OpenCore for instance.

Will get round to extending the script coverage to Sonoma. Also, using dd for bootable disk creation was painful for the modern installers. So I decided to ditch this and ask users to use Etcher themselves. Will look at dealing with that later.
 
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I see. Apple seemed to *imply* it was El Capitan here https://support.apple.com/101578 although I note they did not actually state so. I expect it was introduced with the "*.app" installers which I know Yosemite has and possibly Mavericks.
I have a Install OS X Mavericks.app
I searched all the installers for the createinstallmedia command:
Code:
cd "/Volumes/Updates/System Software"
find . -name 'createinstallmedia' -path '*/Mac OS X*'

One negative about simply running createinstallmedia is that the resulting bootable disk can only be used on units that support that Mac OS version. So, you cannot create a Catalina installer with createinstallmedia and run this on cMP.
Right. It would have to be patched.
https://www.macrumors.com/how-to/install-macos-catalina-unsupported-mac/
https://forums.macrumors.com/threads/macos-10-15-catalina-on-unsupported-macs.2183772/

The Install_USB_Maker script reconstitutes the installers after stripping the supported unit and other requirements such as certs out before creating the bootable disk (Legacy *.dmg Installers ... Lion to LoSierra) or dumping the ISO for burning (Modern *.app Installers ... Yosemite to Monterey). Such can then be used for installation via OpenCore for instance.

Will get round to extending the script coverage to Sonoma. Also, using dd for bootable disk creation was painful for the modern installers. So I decided to ditch this and ask users to use Etcher themselves. Will look at dealing with that later.
I'm not sure I ever tried using OpenCore to boot an unpatched Catalina Installer on an unsupported Mac. I used the dosdude patchers from Sierra to Catalina for a Mac Pro 2008.
 
Not sure I ever tried using OpenCore to boot an unpatched Catalina Installer on an unsupported Mac
Catalina was just an example chosen because it was the first that is not supported on any cMP ... which I wanted to use as an example unit type. The "2010 to 2020 era" units of the OP will not all be cMP or might not even include any.

The premise though, was that someone creating a multi-installer disk would want the option to be able to run such on as many supported/unsupported scenarios as possible. I suppose it could be that only supported versions would ever be installed and the limitation wouldn't matter but other readers might want to consider that angle.

I use OpenCore for unsupported Mac OS on my MP31 ... Tiger (thanks for helping with this) and LoSierra to Monterey with the exception of Catalina which is via a DosDude patched instance. DosDude Catalina serves as a "pseudo-natively-bootable" instance so that I can recover if needed without having to swap my RX580 out for HD5770.

I do not have a multi-installer disk of the kind discussed and just have the download packages from which I created uni-installer disks when I was installing Tiger to Monterey last year. Might be worth creating such a multi-installer at some point but saw the installation thing as more of a one-off at the time and on just one unit. OP seems to have a bunch of units and different calculations there.

Also already had OpenCore set up and as MyBootMgr creates one instance for installations/updates, I just created the boot sticks one by one and ran them as needed using OpenCore for the unsupported instances (apart from Catalina). With OpenCore, given my GPU and cMP models, I didn't need filesystem patches but will do so if/when I go beyond Monterey.

I suppose DosDude installers can also be used in a multi-installer stick for the relevant instances although I found the LoSierra to Mojave versions to be flaky when I went through the process last year. Not sure why as I had used DosDude HiSierra and Mojave without issue in the past. DosDude Catalina went smoothly. I always boot this one via RefindPlus.
 
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I suppose DosDude installers can also be used in a multi-installer stick for the relevant instances although I found the LoSierra to Mojave versions to be flaky when I went through the process last year. Not sure why as I had used DosDude HiSierra and Mojave without issue in the past. DosDude Catalina went smoothly. I always boot this one via RefindPlus.
True. A multi installer disk can include helper FAT or HFS+ partitions containing Dosdude booters, Open Core, RefindPlus, etc.
 
I have made dozens of installer drives, and have been making multiple installer drives since Lion appeared.
I have a few with everything from Leopard to Sonoma on one drive. (It's a hobby...:cool: )
All use standard GPT with HFS+ partitions.
I think this will be changing soon, as there is a limit on one device of 16 HFS partitions.
but, I have recently been making what I call "modern macOS": High Sierra to Sonoma
Those are the ones that are most useful now.

I used to carefully craft the size of each individual installer partition, so there was only about 60MB of free space on each volume. I can get all installers from Leopard to Mojave, 10 partitions bootable, on one 64GB flash drive.
Can't do that with the "modern" systems -- but, then I also do this on NVME drives, with a 500GB often less than $40, no need for best quality/speed for this use, and much faster file transfer speeds (compared to thumb drives)
Can you please share your process to do this; create multiple bootable macOS installers in on USB or NVME drive? Also, if you say how you get the installers, that would be great. Apple now offers the 'old' installers but not the following, which must be had from the store, for example. However, direct downloads for these, if you know, would be good:
Sequoia 15
Sonoma 14
Ventura 13
Monterey 12
Big Sur 11
Catalina 10.15
Mojave 10.14
High Sierra 10.13

And more interestingly, it will be good to know if your process will work with Open Legacy Patcher. Thanks a lot!
 
I use the application "Mist", which offers those macOS installers that you listed, plus older installers back to OS X 10.7.5 (Lion). The only exception is 10.9.5 (Mavericks), which is an interesting challenge to acquire. Other than Mavericks, you can download all Mac systems from Lion to current Sequoia. I have installer drives, sometimes with only a single bootable system installer, others with multiple OS X/macOS bootable installers. Some have Leopard to Sonoma, others, I start with later versions, such as High Sierra (the first version that fully supports SSDs with APFS, making me consider High Sierra as the beginning of "modern" macOS. So, the installers that I use most ofter start there, and I have several sets, now going from macOS 10.13.6 to Sequoia 15.2
I don't use the OpenCore Legacy Patcher app to make bootable installers. I could, but just don't use it. I am sure it would work fine, and I have 4 or 5 Macs that I maintain as OCLP systems. I simply use the normal Terminal commands to make bootable installers, as I need them. I have a list of the install space that I need for each macOS version, but it also works fine to just add 1 GB to the size of the installer app, make a volume that size, then use that as the destination for the setup of the bootable installer. I use a drag-n-drop method to actually make the installer, so only takes a few seconds to set up the install, then the longest time is waiting for the installer to finish in my terminal.
So, this is the process that I use:
Erase the drive that I want to use. Add partitions to that drive, making each partition the size that is needed for each individual bootable installer. Setup each bootable installer, making each installer, one at a time. So, 10 different macOS system installers means 10 partitions on that drive, as a minimum.
If you want to work with OS X versions older than 10.10, you will need to use other steps, such as copying installer DVDs, and other steps might be involved. After Yosemite or El Capitan, then usual terminal commands may be all you need, and there's several dedicated apps that will also do the job.
 
I use the application "Mist", which offers those macOS installers that you listed, plus older installers back to OS X 10.7.5 (Lion). The only exception is 10.9.5 (Mavericks), which is an interesting challenge to acquire. Other than Mavericks, you can download all Mac systems from Lion to current Sequoia. I have installer drives, sometimes with only a single bootable system installer, others with multiple OS X/macOS bootable installers. Some have Leopard to Sonoma, others, I start with later versions, such as High Sierra (the first version that fully supports SSDs with APFS, making me consider High Sierra as the beginning of "modern" macOS. So, the installers that I use most ofter start there, and I have several sets, now going from macOS 10.13.6 to Sequoia 15.2
I don't use the OpenCore Legacy Patcher app to make bootable installers. I could, but just don't use it. I am sure it would work fine, and I have 4 or 5 Macs that I maintain as OCLP systems. I simply use the normal Terminal commands to make bootable installers, as I need them. I have a list of the install space that I need for each macOS version, but it also works fine to just add 1 GB to the size of the installer app, make a volume that size, then use that as the destination for the setup of the bootable installer. I use a drag-n-drop method to actually make the installer, so only takes a few seconds to set up the install, then the longest time is waiting for the installer to finish in my terminal.
So, this is the process that I use:
Erase the drive that I want to use. Add partitions to that drive, making each partition the size that is needed for each individual bootable installer. Setup each bootable installer, making each installer, one at a time. So, 10 different macOS system installers means 10 partitions on that drive, as a minimum.
If you want to work with OS X versions older than 10.10, you will need to use other steps, such as copying installer DVDs, and other steps might be involved. After Yosemite or El Capitan, then usual terminal commands may be all you need, and there's several dedicated apps that will also do the job.
thanks a lot! your mention of 'mist' also is great. thanks a lot.
 
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