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glossywhite

macrumors 65816
Original poster
Feb 28, 2008
1,120
3
This is how Lion works, and how it WILL install - if I am wrong, I'll give you a cheesecake!:

1/ You run the installer app
2/ Installer app asks where you wish to install
3/ Regardless of your chosen drive/volume, Lion creates a "restore" partition (think of it as equivalent to the install DVD)
3b/ Installer app reboots the Mac, and temporarily boots from the "restore" partition which it created in *phase 1* of the installation

4/ If you didn't choose a volume different to the one from which you were booted when you ran the installer, Installer app *phase 2* will ask if you wish to upgrade OR clean install (note: phase 2 runs from "restore" partition that *phase 1* created, before it rebooted, so that the installer can complete the process. THIS PARTITION IS HIDDEN - YOU WON'T SEE IT IN DU - doesn't mean it isn't there! ;)

It seems you need ONLY to copy the Installer app, and NOT the right-click >> extract DMG method (ridiculous notion that this would be expected of HOME USERS!) to another Mac to install, after having copied it from a Mac which had/has Mac App Store access, in order to install on other Macs.

Am I wrong? Unlikely - seems MOST people think differently, which is why most people are getting totally muddled - over-analysis coupled with very little/no knowledge of how Mac OS X and computer systems in general partition disks/restore partitions, is likely causing all this FUD.

[EDIT]

You can boot from the recovery partition, open Disk Utility and erase other partitions, including the one to which you installed Lion, so there IS a hidden recovery partition of sorts - I've just watched someone do this!!

A)
If you erase the partition onto which you installed Lion, using the "restore" partition version of DU, and then boot into SL, open SL DU and highlight the Lion partition you just erased, VISUALLY it shows it is all empty space (no blue bar) but in the size description, 5-6Gb is missing... ;)

B) If you use SL DU and highlight the Lion partition, and click (-) to remove it, and once done, drag the SL slider RIGHT DOWN to fill the free space, and then reboot holding OPT, the "restore" partition has gone, and no option is there to boot from it!

Magic! :D
 

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I have actually NOT been able to boot from the recovery partition manually in DP4, though it is indeed there.

It's used for more than recovery though: "restart to safari" also uses this partition. This I've managed to do.
 
"I have actually NOT been able to boot from the recovery partition manually in DP4, though it is indeed there."

I just did that.

Try this:
1. Restart
2. As soon as you hear the startup sound, hold down the Option key and KEEP HOLDING IT DOWN. This invokes the Startup Manager
3. Wait a few seconds, you should see a row of volume icons
4. One of these should be named "Recovery HD"
5. Click ONE time on Recovery HD to select it, then hit the "Enter" key.

What happens next?
 
I think where you are wrong is first the recovery partition is supposedly only 800MB that can't hold all of Lion.

And second and more importantly, there are conditions where the recovery partition cannot be made, yet Lion still installs fine.
 
"I have actually NOT been able to boot from the recovery partition manually in DP4, though it is indeed there."

I just did that.

Try this:
1. Restart
2. As soon as you hear the startup sound, hold down the Option key and KEEP HOLDING IT DOWN. This invokes the Startup Manager
3. Wait a few seconds, you should see a row of volume icons
4. One of these should be named "Recovery HD"
5. Click ONE time on Recovery HD to select it, then hit the "Enter" key.

What happens next?

Yes, I'm well aware of how top invoke the startup manager. I've only been doing this for 15-odd years now :p

Anyway, my laptop (MacBookPro5,3) does not show a recovery partition in the startup manager, nor in Startup Disk, nor in Disk Utility. Commandline disk utility does show it and allows me to mount it. It's obviously bootable though, because as I said "Restart to Safari" works fine and that works off that partition.
 
This is how Lion works, and how it WILL install - if I am wrong, I'll give you a cheesecake!:

1/ You run the installer app
2/ Installer app asks where you wish to install
3/ Regardless of your chosen drive/volume, Lion creates a "restore" partition (think of it as equivalent to the install DVD)
3b/ Installer app reboots the Mac, and temporarily boots from the "restore" partition which it created in *phase 1* of the installation

What happens if the disk is currently partitioned in a way that there is no way to create this restore partition? Suppose the entire disk is filled with a single partition, which cannot be shrunk?

I seriously think that this "restore" partition will come into existence only on clean installs to an empty disk.
 
What happens if the disk is currently partitioned in a way that there is no way to create this restore partition? Suppose the entire disk is filled with a single partition, which cannot be shrunk?

I seriously think that this "restore" partition will come into existence only on clean installs to an empty disk.

No, it appears it adds it always. There are few ways in which the single partition on disk can not be shrunk. So long as the space is available, it should be doable. If the space isn't available, it'll probably just error and tell you to free up some space. Remember: this is at the end of the disk (or partition), so there should be no OS files there that can't be moved.
 
3b/ Installer app reboots the Mac, and temporarily boots from the "restore" partition which it created in *phase 1* of the installation

You owe me a cheesecake. According to Apple, Lion will install without the need for a reboot. I believe technically, you have to reboot after the installation is done. Still, Lion will be installed from the installer, not the restore partition.

It seems you need ONLY to copy the Installer app, and NOT the right-click >> extract DMG method (ridiculous notion that this would be expected of HOME USERS!) to another Mac to install, after having copied it from a Mac which had/has Mac App Store access, in order to install on other Macs.

Yes, Apple has stated as much already. The extraction of .dmg method is not Apple-sanctioned anyhow, just something discovered by exploratory users. Besides, the point of extracting the .dmg was to have a bootable device to install Lion from, not to be able to install Lion on multiple Macs (though that is a side benefit). So, no, users are not expected to know or figure out this method.

You doubly owe me a cheesecake.

Am I wrong? Unlikely - seems MOST people think differently, which is why most people are getting totally muddled - over-analysis coupled with very little/no knowledge of how Mac OS X and computer systems in general partition disks/restore partitions, is likely causing all this FUD.

You're at least partially wrong :p You may not be contributing to FUD, but you are spreading some misinformation.
 
You owe me a cheesecake. According to Apple, Lion will install without the need for a reboot.

This isn't true. It starts installing without a restart (setting up the recovery partition) but it does most of the job after restarting.

What Apple means by "Installing in Place" is that you don't have to copy the installer to something else and boot from that to start the install. You just start it right on the install disk.
 
This isn't true. It starts installing without a restart (setting up the recovery partition) but it does most of the job after restarting.

What Apple means by "Installing in Place" is that you don't have to copy the installer to something else and boot from that to start the install. You just start it right on the install disk.

In the Keynote, the speaker said (I'm paraphrasing here): "You can install Lion without rebooting". The research I've done around the web suggests that the install will complete before the restart is necessary.

Regardless, my point that the install does not come off the recovery partition like the OP suggested still stands ;)
 
I've done the install myself and can confirm it restarts. What Schiller meant is that you don't have to restart from a DVD or external.
 
I've done the install myself and can confirm it restarts. What Schiller meant is that you don't have to restart from a DVD or external.

I remember him saying that as well and thinking, huh? He obviously meant the initial install would be without reboot. You can't change OSs without a reboot.
 
You can't change OSs without a reboot.

Not entirely true. Linux has developed a way to do in-place kernel updates without the need to reboot. While I'm pretty sure the Mach kernel doesn't do this, it doesn't mean it's not possible. If the kernel wasn't updated, then you could even more easily do it, as a simple log out/in should suffice. That would provide a point at which, theoretically, the kernel could unload pretty much all the old stuff and load in the new stuff.

Where's my cheesecake?! :confused:
 
Not entirely true. Linux has developed a way to do in-place kernel updates without the need to reboot. While I'm pretty sure the Mach kernel doesn't do this, it doesn't mean it's not possible. If the kernel wasn't updated, then you could even more easily do it, as a simple log out/in should suffice. That would provide a point at which, theoretically, the kernel could unload pretty much all the old stuff and load in the new stuff.

Almost. I'll assume you mean Linux's kexec method. While you aren't rebooting the machine itself, you are shutting everything down and having the old kernel launch a new kernel, after which the regular OS boot process of launching init starts. So while technically it might not be a reboot, it certainly is practically as the process is exactly the same, with the exception of skipping the step where the machine itself restarts.

In theory, there isn't that much preventing Apple from implementing the same thing in OSX. The XNU kernel could exec a new XNU kernel (which most definitely changes between OS releases, btw) and the new XNU would call launchd as always. In reality however you gain almost nothing by doing this but you do add a whole lot of complexity. I still don't really know why it was added to Linux, beyond 'look what we can do'.

Also, a log in/out does not suffice when the entire system underneath you has changed. At the very minimum, you'd have to shut everything down and make launchd re-exec its newly-upgraded self as if the system were being booted. The above applies: nothing is gained, lots of complexity is added.
 
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