I've done further experimentation. It appears that, with the installers that were refreshed in 2019, with new certificates, some changes actively toxic to DVD booting were added.
I burned a couple more "coasters" (disks useless for data, and to be kept under beverages. I tried a hybrid of "Use the createinstallmedia command" from the Apple Documentation: Create a bootable installer, and the recipe from colt2 where I carefully created an image of small enough size of type Apple Partition Map.
I used dd to put the resulting image onto a usb drive, and it worked perfectly.
I burned it onto a DVD with the following results:
Starting that up, I got the error, saying it could not run and to, "Copy this application to a writeable Mac OS Extended Formatted disk and reopen."
So the hand copy from the earlier recipes don't seem to work.
The createinstallmedia doesn't work either.
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Here are more details on my experience with using the colt2 method as repeated above by @VaZ :
The first time I booted the dvd, after about 20 minutes I got the Language Selection menu, not the utilities splash screen, and "Install MacOS was running." So I went forward a couple screens and then backed out, and quit the Installer.
Then I got the utilities splash screen and menus.
I ran disk utility to confirm it would run.
I forget if I re-ran the installer.
It was late, so I went to bed feeling happy that I'd gotten a working install disk.
The next morning I tried booting from the disk.
It ran for 20 minutes or so, and then the DVD drive stopped spinning, and there it seemed to sit and sit and sit.
The DVD drive spun down.
For a while after that I poked at it.
Unplugging and re-plugging the power cable could wake the DVD drive up for a moment, but it never booted.
I'm not sure how long I waited for start-up before I gave up.
I tried booting from power off, from a restart with El Capitan running, etc. No boot.
I have no idea why the boot worked the first time!
I've just retried booting from that disk. I'm going to bed now, and will let it grind through the night with the expectation that nothing will happen.
I burned a couple more "coasters" (disks useless for data, and to be kept under beverages. I tried a hybrid of "Use the createinstallmedia command" from the Apple Documentation: Create a bootable installer, and the recipe from colt2 where I carefully created an image of small enough size of type Apple Partition Map.
I used dd to put the resulting image onto a usb drive, and it worked perfectly.
I burned it onto a DVD with the following results:
- After about 5 minutes the progress bar was one/third filled. I thought maybe this would work.
- After about 20 minutes it looked we were in infinite loop land like with the original failure mode.
- After about 30 minutes I got utilities!
- But no utilities were selectable.
- I poked around and after showing and hiding the log file (which was filled with font failures about TSplicedFont).
- I then starting and quitting terminal from the menu
- FINALLY, I got utilities that enabled me to select "Install MacOS".
Starting that up, I got the error, saying it could not run and to, "Copy this application to a writeable Mac OS Extended Formatted disk and reopen."
So the hand copy from the earlier recipes don't seem to work.
The createinstallmedia doesn't work either.
----
Here are more details on my experience with using the colt2 method as repeated above by @VaZ :
The first time I booted the dvd, after about 20 minutes I got the Language Selection menu, not the utilities splash screen, and "Install MacOS was running." So I went forward a couple screens and then backed out, and quit the Installer.
Then I got the utilities splash screen and menus.
I ran disk utility to confirm it would run.
I forget if I re-ran the installer.
It was late, so I went to bed feeling happy that I'd gotten a working install disk.
The next morning I tried booting from the disk.
It ran for 20 minutes or so, and then the DVD drive stopped spinning, and there it seemed to sit and sit and sit.
The DVD drive spun down.
For a while after that I poked at it.
Unplugging and re-plugging the power cable could wake the DVD drive up for a moment, but it never booted.
I'm not sure how long I waited for start-up before I gave up.
I tried booting from power off, from a restart with El Capitan running, etc. No boot.
I have no idea why the boot worked the first time!
I've just retried booting from that disk. I'm going to bed now, and will let it grind through the night with the expectation that nothing will happen.