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El Capitan bootable DVD?
- Thread starter mrogers07
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Yup, pretty much the same as since Mavericks (this for USB devices but almost same for DVD)...
http://www.marekbell.com/how-to-create-a-bootable-installer-for-os-x-el-capitan-10-11/
While those instructions may work for creating a bootable USB stick, the OP - like myself as well - are looking to create a bootable ISO that can later be burned to a DVD if needed. The reason I require or want a proper bootable ISO that actually works is because I use VMware Fusion for a lot of testing with OSX virtual machines and it's not an easy task to get the VMs to boot from a USB stick which must be attached to the VM during the boot process. It's just a chore and another step or two that's irrelevant and shouldn't be necessary to begin with.
I know Apple hates optical media these days and is doing everything they can to avoid such things including the ISO files most all of use to burn to an optical disc for installing their OSes but, it shouldn't be this difficult to create an ISO (or CDR, whichever extension you prefer, it's the same thing overall) from the install app for newer versions.
I know it's a bit of a hack but what I've been doing is create the bootable USB and then just using Disk Utility to make an image of that, which you can then burn to DVD. There is probably a way to go directly to DVD without the USB step, but since I wanted both USB and DVD installers this worked for me.
You can create an image file, use createinstallmedia to put the installer there and then convert it to an iso using the disk utility. No idea if it will give you a bootable DVD in the end, but its worth the try. BTW, the image is too large for a normal DVD, you'd need a DL one.
Not critisising your decision here, but is there any reason why you want to make a DVD over a bootable USB Drive?
In the past, I've always insisted on having a bootable DVD for my OS's, but after using bootable USB sticks, I found DVD to be slow and really old fashioned.
Sure, I still make them, but having a drive is so much quicker and there are loads of ways of making them. I use 'DiskMaker X' and its fully compatible with El Cap.
In the past, I've always insisted on having a bootable DVD for my OS's, but after using bootable USB sticks, I found DVD to be slow and really old fashioned.
Sure, I still make them, but having a drive is so much quicker and there are loads of ways of making them. I use 'DiskMaker X' and its fully compatible with El Cap.
I agree !
In my experience, DVD's tend to stall out the install as the data cannot be delivered rapidly enough. Since 8GB USB thumb drive's can be had for $5 or less, makes much more sense to use one.
Again, the info is right here in the thread (at least with respect to me and my requirements): using USB sticks to boot virtual machines is more trouble than it's worth. Yes, it's possible, but it's not as simple as just plug in a bootable USB stick and tell the VM software to use it as the boot device, it's a bit more complex than that. Even using an actual DVD in an optical drive as part of the physical host machine that's running the guest OS is easier than using a USB stick, I can't say for the life of me why however. I suppose it's just not that big of a deal to the VM developers - it's not a hardware limitation either as I understand it.
Anyway, I'll keep trying various methods and hacks until something comes along that not only explains what has changed with the final release of El Capitan but also provides "the fix" to make ISOs if desired.
Anyway, I'll keep trying various methods and hacks until something comes along that not only explains what has changed with the final release of El Capitan but also provides "the fix" to make ISOs if desired.
Br0adband, earlier today I completed a new online tutorial regarding how to install and run a VirtualBox/Mountain Lion/SheepShaver/Mac Classic environment on an El Capitan iMac. One section which might be of interest to you, and which may possibly solve your problem, is called "VII. CREATE A MOUNTAIN LION 10.8 BOOTABLE DVD".
It explains how I used an installESD.dmg image to create a bootable DVD of Mountain Lion for VirtualBox.
You may want to have a look at it at the following URL and see if it helps in your situation:
http://www.armageddonbbs.com/VirtualBox-Mountain-Lion-SheepShaver-Setup-Guide.html
I wish you the best.
Mavericks, yosemite and el capitan changed so that just burning the InstallESD.dmg won't give you a bootable dvd.
Also, restoring a bootable usb to iso results in a bootable iso, but that iso is useless because booting is ALL it does. Try actually installing from it and it doesn't work.
There are 12 and 14 terminal commands respectively to make a bootable iso and dvd for mavericks and yosemite respectively. It is THIS version of the iso which has been successful for mavericks and yosemite. So far attempts to tweak these for the public release of el capitan have not worked because apple have changed it yet again.
There is another thread with more details on this here: https://forums.macrumors.com/threads/how-to-create-el-capitan-os-x-bootable-dvd.1923894/
Also, restoring a bootable usb to iso results in a bootable iso, but that iso is useless because booting is ALL it does. Try actually installing from it and it doesn't work.
There are 12 and 14 terminal commands respectively to make a bootable iso and dvd for mavericks and yosemite respectively. It is THIS version of the iso which has been successful for mavericks and yosemite. So far attempts to tweak these for the public release of el capitan have not worked because apple have changed it yet again.
There is another thread with more details on this here: https://forums.macrumors.com/threads/how-to-create-el-capitan-os-x-bootable-dvd.1923894/
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This code worked for me.
It was done with the terminal utility.
It seems there was code that was included in the O/S to dissuade the creation of optical discs though.
The reason being that during the installation,toward the end of the boot process it freezes.
Here's the code anyway.Maybe someone else can tweak it to make it work.
On the last line,it starts with "sudo",replace "YOURNAME" with the username for the account you are logged into at the time.
hdiutil attach /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/SharedSupport/InstallESD.dmg -noverify -nobrowse -mountpoint /Volumes/install_app
hdiutil convert /Volumes/install_app/BaseSystem.dmg -format UDSP -o /tmp/El\ Capitan
hdiutil resize -size 9g /tmp/El\ Capitan.sparseimage
hdiutil attach /tmp/El\ Capitan.sparseimage -noverify -nobrowse -mountpoint /Volumes/install_build
rm /Volumes/install_build/System/Installation/Packages
cp -rp /Volumes/install_app/Packages /Volumes/install_build/System/Installation/
cp -rp /Volumes/install_app/BaseSystem.chunklist /Volumes/install_build
cp -rp /Volumes/install_app/BaseSystem.dmg /Volumes/install_build
hdiutil detach /Volumes/install_app
hdiutil detach /Volumes/install_build
hdiutil resize -size `hdiutil resize -limits /tmp/El\ Capitan.sparseimage | tail -n 1 | awk '{ print $1 }'`b /tmp/El\ Capitan.sparseimage
hdiutil convert /tmp/El\ Capitan.sparseimage -format UDTO -o /tmp/El\ Capitan
rm /tmp/El\ Capitan.sparseimage
mv /tmp/El\ Capitan.cdr ~/Desktop/El\ Capitan.iso
sudo drutil burn /Users/YOURNAME/Desktop/El\ Capitan.iso
Yeah. You seem to have solved it. This definitely works to make a bootable dvd.
The ultimate test of the dvd though isn't just that it boots up, but also is capable of installing the system.
I already had a clean install of el capitan on a partition which I made with my bootable usb but decided to wipe it to thoroughly test the el capitan dvd. Of course the dvd boots up much more slowly than the usb, as expected. But the dvd successfully installed el capitan.
The iso file still can't be used to install into vmware fusion however.
I posted instructions in the other thread for how to install into vmware fusion using the installer app instead of the iso: https://forums.macrumors.com/thread...itan-os-x-bootable-dvd.1923894/#post-22017415
The ultimate test of the dvd though isn't just that it boots up, but also is capable of installing the system.
I already had a clean install of el capitan on a partition which I made with my bootable usb but decided to wipe it to thoroughly test the el capitan dvd. Of course the dvd boots up much more slowly than the usb, as expected. But the dvd successfully installed el capitan.
The iso file still can't be used to install into vmware fusion however.
I posted instructions in the other thread for how to install into vmware fusion using the installer app instead of the iso: https://forums.macrumors.com/thread...itan-os-x-bootable-dvd.1923894/#post-22017415
May I ask what VM software you're using?
I've used a USB stick as an installer to put Windows in VirtualBox and Fusion. Both were quite easy to do.
VMware Fusion 8.0.1 at this moment, and yes I'm aware of being able to use a USB stick but as stated previously using an ISO is more efficient since it's already on the storage so pulling it will be faster than any USB stick available today (yes, even the best USB 3.0 sticks would probably be slower). It's a personal thing, not an absolute must - the basic gist of it is that I don't like some of the changes that Apple keeps making (that are not really improving things and were innocuous to begin with) and so I have to find workarounds for those changes (that is more hassle for me, the end user).
The thread is about making a bootable DVD; I jumped in to say I wanted a bootable ISO which can be used to make bootable DVDs, etc so the methodology is very similar in most respects.
I'll test out that method outlined just above that tywebb13 says is bootable, and hope for the best.
EDIT:
And as tywebb13 noted, it is not bootable in Fusion, sadly. The quest continues...
The thread is about making a bootable DVD; I jumped in to say I wanted a bootable ISO which can be used to make bootable DVDs, etc so the methodology is very similar in most respects.
I'll test out that method outlined just above that tywebb13 says is bootable, and hope for the best.
EDIT:
And as tywebb13 noted, it is not bootable in Fusion, sadly. The quest continues...
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Hello br0adband,
I found this thread as I too was looking for a bootable ISO image of ElCap as I am a bit of a VM guy myself. Sadly I discovered that all the old Mavericks and Yosemite stuff didnt work, but after much testing (in VMs of course!) I now DO have a fully bootable and working ISO of ElCap. I registered with MacRumors just to post this, so hopefully you (all) find it useful. I am going to list the steps in a rather verbose manner to avoid any confusion but you will see it is rather simple after all. BTW this is tested and working in VMWare Fusion 8.0.1 running on ElCap host.
I strongly suggest doing this in (a VM of!) Mavericks or Yosemite as the old DiskUtility has the ability to create a CUSTOM SIZED image file, and I wanted to do that to make it as small as possible, rather than a wasteful 8.3Gb - mine comes in at 6.97Gb file. The ElCap DiskUtility is rather too FisherPrice for my liking! This all assumes you have the El Capitan Installer app which will be our source.
Hope you found this useful. BTW I will check this forum for the next week or so in case of any replies but after that you will likely have to PM me.
Kind regards to all.
I found this thread as I too was looking for a bootable ISO image of ElCap as I am a bit of a VM guy myself. Sadly I discovered that all the old Mavericks and Yosemite stuff didnt work, but after much testing (in VMs of course!) I now DO have a fully bootable and working ISO of ElCap. I registered with MacRumors just to post this, so hopefully you (all) find it useful. I am going to list the steps in a rather verbose manner to avoid any confusion but you will see it is rather simple after all. BTW this is tested and working in VMWare Fusion 8.0.1 running on ElCap host.
I strongly suggest doing this in (a VM of!) Mavericks or Yosemite as the old DiskUtility has the ability to create a CUSTOM SIZED image file, and I wanted to do that to make it as small as possible, rather than a wasteful 8.3Gb - mine comes in at 6.97Gb file. The ElCap DiskUtility is rather too FisherPrice for my liking! This all assumes you have the El Capitan Installer app which will be our source.
- Right-click the installer app, and choose Show Package Contents from the resulting contextual menu.
- In the folder that appears, open Contents, then open Shared Support; you’ll see a disk image file called InstallESD.dmg.
- Double-click InstallESD.dmg in the Finder to mount its volume. That volume will appear in the Finder as OS X Install ESD; open it to view its contents.
- SHOW hidden files (use a small app like me or use the Terminal command easily found on Google)
- Launch Disk Utility and then drag BaseSystem.dmg (in the OS X Install ESD volume) into Disk Utility’s left-hand sidebar.
- Select BaseSystem.dmg in Disk Utility’s sidebar, and then click the Restore button in the main part of the window.
- Drag the BaseSystem.dmg icon into the Source field on the right (if it isn’t already there).
- Make a NEW BLANK DISK IMAGE: CD master, 7316Mb, Apple Partition Map and use the new mount as destination drive (I named it "Bootable El Capitan"). Note the custom size is as small as you can go and fit it all in. Apple Partition Map otherwise will become GUID and be unbootable (yep!), and CD master to give us a cdr file which we will rename to iso. THESE details are the secret sauce that cracked the puzzle for me!
- In Disk Utility, find this newly mounted destination drive in the left sidebar. Drag to the Destination field on the right.
- Click Restore, and then click Erase in the dialog box that appears; if prompted, enter an admin-level username and password.
- Wait for the restore procedure to finish, which should take just a few minutes.
- Open the destination drive, which has been renamed OS X Base System. Inside that drive, open the System folder, and then open the Installation folder. You’ll see an alias called Packages. Delete that alias.
- Open the mounted OS X Install ESD volume (from the installer app), and you’ll see a folder called Packages. Drag that folder into the Installation folder on your destination drive. (You're replacing the deleted Packages alias with this Packages folder.) The folder is about 5.7GB in size, so the copy will take a bit of time.
- Also in the mounted OS X Install ESD volume, you’ll find files named BaseSystem.chunklist and BaseSystem.dmg. Copy these files to the ROOT (top most) level of your destination drive (OS X Base System, not into the System or Installation folder).
- Eject the OS X Install ESD volume (the source one from the installer app, as not needed any more)
- HIDE hidden files (keep things clean!)
- RENAME your 'destination' drive into something cosmetic like "Bootable El Capitan" and then EJECT it to 'close it all up' and now the resultant .cdr file can be renamed into something.iso which you will now find is a fully free standing and bootable ISO image that VMWare Fusion can happily take.
Hope you found this useful. BTW I will check this forum for the next week or so in case of any replies but after that you will likely have to PM me.
Kind regards to all.
BRAVO, my fellow Mac user, BRA-FREAKIN'-VO... 
The methodology outlined above by asifanwar works and creates a bootable CDR/ISO that is capable of being used to create new virtual machines with VMware Fusion, tested and verified by me just now.
Outstanding, asifanwar, simply outstanding and thank you very much for your efforts in helping to work out that method. I've already backed up that ISO in like 6 locations so it's about as safe as can be but obviously creating a new one - now that the method is known - is a non-issue.
Seriously, thank you, and tywebb13 for pursuing it as well.
Now on to the next little thing...
The methodology outlined above by asifanwar works and creates a bootable CDR/ISO that is capable of being used to create new virtual machines with VMware Fusion, tested and verified by me just now.
Outstanding, asifanwar, simply outstanding and thank you very much for your efforts in helping to work out that method. I've already backed up that ISO in like 6 locations so it's about as safe as can be but obviously creating a new one - now that the method is known - is a non-issue.
Seriously, thank you, and tywebb13 for pursuing it as well.
Now on to the next little thing...
You are very welcome, glad it worked out.
Ironically actually I am a Windows guy! I did all my testing and (many times failed!) installing on VMWare Workstation 12. I work from home on a virtual machine. I am actually a doctor (radiologist) and read xrays, CT scans etc remotely for multiple clients in the USA, and as the geek that I am, I do it all in a VM of Win7x64 using a USB mic and Dragon Medical Practice Edition voice recognition. My host is my own customized stripped down Lite version of Win8.1 (Core i7 5960X 16-core CPU, 32Gb DDR4, 120Gb and 1000Gb SSD drives, GF980GTX GPU attached to 2x 40" 4K Philips LCDs and a 22" AOC 1080p LCD). During the downtime between patients, I spend my time generally being geeky and tinkering a lot in VMs and fiddling around with OSes and apps! Radiology pays the bills, but being a geek is the real job! My host work PC generates significant income and can easily be justified as such a powerful piece of hardware. Of course playing Dishonored at 4K at 40" is all part of my scientific medical research......
I am a big fan of MacOS and my wife and my sister now both finally have Macs after much cajoling and insistence by me as fed up with their endless support questions on Windows! But I fire up a VM of MacOS a fair bit when I want to test something out before fiddling with THEIR systems (or even VNCing into my sister's house to show her something she has enquired about). It is because I am not so familiar with MacOS that these bootable ISOs are of value to me (have them going back to SL10.6) and they have been of use to me in jailbreaking my iPhones in the past too.
Anyway, today is the day I fully update my wife's Mac Mini to ElCap so was keen to get a bootable ISO as ElCap now a 'daily driver' somewhere in my life (sister scared to update during her PhD so still on Mav) and it is likely I will want to do fresh installs from time to time to test something.
I had been fighting with this for a few days and during my Googling found little help but did come across your thread. Once I figured it out I was trying to find this thread again as wanted to come back here and help out as your query was precisely mine and some folks not really understanding why you didnt go for the more typical USB installer. But I quickly installed Fusion on the MacMini and tested my ISO on it to make sure it could work there and not just in Workstation!
Actually, if anyone out there is a MacOS expert, can I ask an off-topic question: how would I get Disk Utility from Yosemite to run in ElCap? I tried fiddling with the version numbers in the plist files but it still refuses to run and tells me to run the (stinky) new version. Changing the entire OS version number is easy of course, but folly as breaks everything else. Any way to do it? Would be very useful!
Anyway, kind regards to all.
Cheers.
Asif
Ironically actually I am a Windows guy! I did all my testing and (many times failed!) installing on VMWare Workstation 12. I work from home on a virtual machine. I am actually a doctor (radiologist) and read xrays, CT scans etc remotely for multiple clients in the USA, and as the geek that I am, I do it all in a VM of Win7x64 using a USB mic and Dragon Medical Practice Edition voice recognition. My host is my own customized stripped down Lite version of Win8.1 (Core i7 5960X 16-core CPU, 32Gb DDR4, 120Gb and 1000Gb SSD drives, GF980GTX GPU attached to 2x 40" 4K Philips LCDs and a 22" AOC 1080p LCD). During the downtime between patients, I spend my time generally being geeky and tinkering a lot in VMs and fiddling around with OSes and apps! Radiology pays the bills, but being a geek is the real job! My host work PC generates significant income and can easily be justified as such a powerful piece of hardware. Of course playing Dishonored at 4K at 40" is all part of my scientific medical research......
I am a big fan of MacOS and my wife and my sister now both finally have Macs after much cajoling and insistence by me as fed up with their endless support questions on Windows! But I fire up a VM of MacOS a fair bit when I want to test something out before fiddling with THEIR systems (or even VNCing into my sister's house to show her something she has enquired about). It is because I am not so familiar with MacOS that these bootable ISOs are of value to me (have them going back to SL10.6) and they have been of use to me in jailbreaking my iPhones in the past too.
Anyway, today is the day I fully update my wife's Mac Mini to ElCap so was keen to get a bootable ISO as ElCap now a 'daily driver' somewhere in my life (sister scared to update during her PhD so still on Mav) and it is likely I will want to do fresh installs from time to time to test something.
I had been fighting with this for a few days and during my Googling found little help but did come across your thread. Once I figured it out I was trying to find this thread again as wanted to come back here and help out as your query was precisely mine and some folks not really understanding why you didnt go for the more typical USB installer. But I quickly installed Fusion on the MacMini and tested my ISO on it to make sure it could work there and not just in Workstation!
Actually, if anyone out there is a MacOS expert, can I ask an off-topic question: how would I get Disk Utility from Yosemite to run in ElCap? I tried fiddling with the version numbers in the plist files but it still refuses to run and tells me to run the (stinky) new version. Changing the entire OS version number is easy of course, but folly as breaks everything else. Any way to do it? Would be very useful!
Anyway, kind regards to all.
Cheers.
Asif
Yeah, I'm a Windows person myself, always have been, always will be, but I basically got handed a MacBook Air (late 2008) recently with a dead SSD (sadly) and a battery that almost exploded just a few days ago (no worries, I removed it before that happened and before any extensive warping of the bottom aluminum plate happened) and so I'm getting back into OSX as it's been a few years. No, this isn't what I do my Fusion work on, that's a MacBook Pro (late 2013) with plenty of RAM for such purposes, but I barely even used it till someone gave me the MBA which sparked some interest all over again. Priimary machine is a Dell Latitude E6420 running Windows 7 Pro x64 but I can test this boot capability with VMware Player 12 which I have installed - and yes I did test the El Capitan.iso I made following your method with that earlier today and it boots there too so, double bonus I suppose.
As for the Disk Utility "swap" I'm going to hazard a guess and say you won't have much if any success due to the rather massive amount of changes "under the hood" with El Capitan, but maybe some coding genius can work a miracle, who knows.
Thanks again and have fun, always...
As for the Disk Utility "swap" I'm going to hazard a guess and say you won't have much if any success due to the rather massive amount of changes "under the hood" with El Capitan, but maybe some coding genius can work a miracle, who knows.
Thanks again and have fun, always...
Okay, I remain a little confused regarding the two very different responses from Nocturnius and Asifanwar.
Nocturnius, you state "This code worked for me.", but then you state the following, as if suggesting that it doesn't really work:
"It seems there was code that was included in the O/S to dissuade the creation of optical discs though.
The reason being that during the installation,toward the end of the boot process it freezes.
Here's the code anyway.Maybe someone else can tweak it to make it work."
So does your code actually work for creating a bootable, functioning DVD installer for El Capitan?
The next poster -- Tywebb13" indicates that it does work:
"Yeah. You seem to have solved it. This definitely works to make a bootable dvd . . . But the dvd successfully installed el capitan."
So which of the two sets of instructions would be better for a person -- such as myself -- who wishes to make a bootable El Capitan installer DVD?
I am kind of leaning towards Asifanwar's method, not only because all of that Terminal work makes me a little nervous, but also because I am already familiar with part of the method that Asifanwar describes, being as I created a bootable Mountain Lion installer DVD only days ago, likewise using a InstallESD.dmg file.
Nocturnius, you state "This code worked for me.", but then you state the following, as if suggesting that it doesn't really work:
"It seems there was code that was included in the O/S to dissuade the creation of optical discs though.
The reason being that during the installation,toward the end of the boot process it freezes.
Here's the code anyway.Maybe someone else can tweak it to make it work."
So does your code actually work for creating a bootable, functioning DVD installer for El Capitan?
The next poster -- Tywebb13" indicates that it does work:
"Yeah. You seem to have solved it. This definitely works to make a bootable dvd . . . But the dvd successfully installed el capitan."
So which of the two sets of instructions would be better for a person -- such as myself -- who wishes to make a bootable El Capitan installer DVD?
I am kind of leaning towards Asifanwar's method, not only because all of that Terminal work makes me a little nervous, but also because I am already familiar with part of the method that Asifanwar describes, being as I created a bootable Mountain Lion installer DVD only days ago, likewise using a InstallESD.dmg file.
The method I mentioned is actually a very simple copy of a few things over, but the key point is to make a "CD master" (ie a cdr file which we rename to iso) but it has to be Apple Partition Map. If you dont then it is my experience that it wont work properly as the disc will come out as a GUID disc instead.
I will try the terminal method listed above and report back my findings.
I will try the terminal method listed above and report back my findings.
If I recall correctly, I had to likewise choose Apple Partition Map when I made my Mountain Lion installer DVD -- I used it to make a Mountain Lion VM for VirtualBox -- because by default, the system wanted to use GUID as well.
However, in that case, because the Mountain Lion InstallESD.dmg file wasn't too far over 4.35 GB -- maybe 4.60 GB perhaps -- it was still able to fit on a single-sided DVD.
In this case, considering the size of El Capitan at 6+ GB, it doesn't seem possible to use a single-sided DVD, and I don't have any dual layer DVD's available at the moment.
Maybe it is old school and old-fashioned, but I still feel a lot safer having my slow DVD backup installer disks. Apple wants to push everything to the cloud, but I really don't like that approach. I like to have what I own on my own hard drive, and nowhere else.
Then there is the issue of privacy and security.
Anyway, I may give your method a try when I next purchase a few dual layer DVD's; whenever that is.
BTW, Asifanwar, in my book, verbose is good!
Check out my own tutorial. I am also VERY verbose.
I tried making an ISO using the method given by user Nocturnius in post#12. It did make an ISO image but that was unbootable for me (Windows 8.1 host, VMWare Workstation 12). It was like all the 'Mavericks, Yosemite' terminal methods I have seen and created a GUID formatted ISO which I cant even read when mounted from the host (can be read fine when mounted within the Mac guest).
My method is the only way I have found that works for mounting and booting the ISO into a virtual machine. Please bear in mind that is and was my goal. I have never burned this to a physical DVD and never booted off a real Mac from that as that is never part of my workflow. It could well be that the terminal method creates a fully workable physical DVD for a real Mac. I am not in any position to comment on that and certainly not trying to offend anyone who has posted with help.
If you are simply looking for optical media backup then maybe easiest to take the installer app (from AppStore), turn into a DMG or ZIP file and then burn that single file to a disc for archiving? Then you always have it to drag off, decompress and use to make a USB thumb for any future reinstalls? Personally I have it on my NAS and is part of my own personal backup workflow on two separate home servers as well as my online 10Tb cloud storage.
Another option is to take that zip/dmg and use one of many free 'file splitters' to break it into smaller pieces then burn those to cheap single layer DVDs (and burn a copy of that app on there too for future use). Easy to drag them all off, join them and decompress back into the installer, then make your USB.
My method is the only way I have found that works for mounting and booting the ISO into a virtual machine. Please bear in mind that is and was my goal. I have never burned this to a physical DVD and never booted off a real Mac from that as that is never part of my workflow. It could well be that the terminal method creates a fully workable physical DVD for a real Mac. I am not in any position to comment on that and certainly not trying to offend anyone who has posted with help.
If you are simply looking for optical media backup then maybe easiest to take the installer app (from AppStore), turn into a DMG or ZIP file and then burn that single file to a disc for archiving? Then you always have it to drag off, decompress and use to make a USB thumb for any future reinstalls? Personally I have it on my NAS and is part of my own personal backup workflow on two separate home servers as well as my online 10Tb cloud storage.
Another option is to take that zip/dmg and use one of many free 'file splitters' to break it into smaller pieces then burn those to cheap single layer DVDs (and burn a copy of that app on there too for future use). Easy to drag them all off, join them and decompress back into the installer, then make your USB.
Actually, I am a Macintosh user of 25+ years. That being the case, I suspect that both your and Nocturnius' methods might possibly work in my situation, being as I don't have the barriers that you do, as a Windows user.
Ironically, even I could not use the Mountain Lion InstallESD.dmg image to install Mountain Lion into a VM in VirtualBox on my own iMac.
I had to follow a special method and burn it to a DVD first so that VirtualBox would recognize it as a valid DVD installer.
Ironically, even I could not use the Mountain Lion InstallESD.dmg image to install Mountain Lion into a VM in VirtualBox on my own iMac.
I had to follow a special method and burn it to a DVD first so that VirtualBox would recognize it as a valid DVD installer.
I guess it depends what you want to use the iso for.
If you want to just burn the dvd, Nocturnius' method is good. I used it to make a dvd, which I got to boot up AND install el capitan.
Another reason I prefer Nocturnius' method is that it does not require you to unhide hidden files.
I also tested the resulting iso for fusion and it didn't work for that. So if you are going to install into fusion, then use asifanwar's method instead.