Shirt Pocket Discussions

Shirt Pocket Discussions (
-   General (
-   -   Boot from sandbox or just use it as a backup. (

fred 04-24-2006 09:47 AM

Boot from sandbox or just use it as a backup.
I've printed out and read the whole 50 page manual and I'm a little confused about the sandbox feature.

At the moment because I didn't fully understand, I just made a full clone of my entire hd and I've been smart updating it.

The manual strongly suggests that this sandbox is used as a boot volume to leave the hd untouched. That's fine, but when I was reading about the cloning options I got confused about the bit where user installed applications are *shared*.

Say for example I decide to now use this new cloned hd as a sandbox and I boot from it.

If I now do a System update and it is fine it of course wouldn't have updated my hd, as that is the whole point. But once I've decided it's good, then I naturally want my hd to be updated too. This is where I'm confused. After it's been ok'd does that mean I sort of do a reverse smart update that makes my hd the same as the clone?

And is this the same for apps I've installed myself? I'm confused about the bit where user installed applications are shared, with an alias. Does that mean the app is on the hd and an alias is on the clone. If so does that mean that when I do a user installed software update it installs to the hd or the clone?

dnanian 04-24-2006 10:07 AM

You definitely don't want to use the Sandbox as a backup, Fred. It's a "system checkpoint" -- a safe place to "play".

So -- if you install a system update, and it's OK, you can follow the instructions to copy back with the reverse smart update as described. And this will also update any applications you've installed yourself on the Sandbox.

It's up to you where you'd like to install a manual application. If you drop it in Applications on the main drive, and you're sharing applications, the alias/symlink will point to the new version. If you replace the alias/symlink in Applications on the Sandbox, it'll be on the Sandbox only unless you copy back.

Make sense?

fred 04-24-2006 10:54 AM

What bothered me about booting and using the sandbox as a boot drive is that the drive would be running all day maybe for at least 12 hours a day! Wouldn't that be bad for an external drive. I'm not sure what they are designed to withstand before they fail.

I gathered from reading the documentation that if the sandbox was just used to be a backup drive then it says in the documentation that it is takes longer to track down the problem and restore everything, whereas with the sandbox as the boot disk you can be back up in minutes by just going back to the hd.

So does that mean if there was an install that buggered the sandbox, one would finish working on the hd and then restore the sandbox via the hd at a more convenient time, to how it was before the bad update and wait for a new good update?

I wasn't clear about the reverse update but now I can see how it works. So the question for me is, is it worth running from my external hd all day long. I work from home which is why I have my computer running for so many hours a day. To answer this I need to know how difficult is it to fix everything if I use the sandbox purely as a back up. For example say the sandbox has been smart updated from my hd and is identical, then I download a piece of user installed softeware and it wreaks havok. Couldn't I then just use the sandbox backup to do a smart update to restore my hd? I don't understand yet what is wrong with this, apart from having to wait for the smart update to update, which wouldn't take more than a half an hour?

Am I missing something here, is it just a matter of being able to get back to work withing a couple of minutes against half an hour? or is there more to it. Because if it's only about a half an hours wait in the unlikely event of something bad happening then it doesn't seem worth it to run the external drive into the ground.

dnanian 04-24-2006 11:01 AM

High quality external drives aren't any more susceptible to "usage problems" than internal drives, Fred.

If you end up installing an update that was incompatible with your system, you would indeed just boot back to the original drive. That'll effectively uninstall the update (because it was never installed on the original drive), so you can get right back to work... and know to avoid the update until whatever incompatibility was there had a workaround.

Again: a Sandbox is NOT a backup. Your user files are not present on it. They're on the original hard disk. You must have a real backup as well...

fred 04-24-2006 11:08 AM

I think I'm using the wrong terminology here, sorry maybe I shouldn't have referred to it as a sandbox. What I've done so far is a full complete copy of my hd. All the userfiles and everything are on it. I've tested it by plugging it into another computer and it's a complete clone of my hd.

But from what I understand I am able to boot from it at anytime and turn it into a proper sandbox. Or have I just got this completely wrong? Do I need to re read the manual again more carefully.

Or is a sandbox only called that when it uses alias for userfiles.

dnanian 04-24-2006 11:53 AM

Ah. That's definitely not a Sandbox. A Sandbox is created with the "Sandbox..." scripts. You can't turn it into a "proper" sandbox without using the Sandbox scripts.

If you boot from a backup, nothing is "shared", so, changes you make on the backup STAY on the backup, even changes to user files...

DaleMeyn 04-24-2006 04:27 PM

Maybe it’s less confusing to visually compare the contents of Sandbox with those of the internal HD.* If you directly open the internal HD (“Mac HD”) by double-clicking on its icon on the desk top, and look at its Applications folder, you will see the list of what’s actually in Mac HD.* Note that none are shown as aliases (no little curved arrows at bottom left of the icons).* Do the same for the Sandbox HD (double-click on its icon on the desktop, not from the opened window), look in its Applications folder, you will see that many applications are actually aliases (marked by the little hooked arrows at bottom left of the icons).
** * Do the same experiment for your Home folder:* open the Users folder for the Mac HD, and note that the Home folder icon is “real” in the Mac HD, but only an alias in the Sandbox HD.
* * The above experiments tell you that your user applications (installed on Mac HD before Sandbox was created) and all your user files in the Home folder (Documents, Pictures, etc.) are not actually saved on the Sandbox HD.* When you boot from the Sandbox, and open the Home folder (via its alias on Sandbox), you’re actually now opening and saving documents to and from the original Home folder on the internal HD (Mac HD.)* However, all of OSX and its “system-owned” applications and files (like Safari, Mail, Library, etc.) are on Sandbox.
* * If, while booted from Sandbox, you install a new application like SuperDuper! it goes in Sandbox, not in Mac HD.* After you decide that it’s compatible and you like it, you can then boot up from Mac HD and install it there also.* Or stay in Sandbox and just copy back (using "Copy all files" and during copy “Smart Update”).* That will also copy to Mac HD any other apps you’ve installed on Sandbox, and any System updates made since the last “back copy”.* One advantage of copying back is that your preferences for SD!, etc., are also transferred to Mac HD.
* * The big advantage of all this is, that if something messes up Sandbox, no problem, just re-boot to Mac Hd (which is unaffected), and update Sandbox per User’s Guide p. 37.* If you’d been operating from Mac HD when a blowup happened, you’d have to recreate its contents, which could be mostly done from your latest full backup (NOT Sandbox!!), but wouldn’t include any of your work since that last backup.* Remember, when operating in Sandbox, all your work is saved to Mac HD, not Sandbox, which only keeps the alias of the Home folder, whose contents reside in the original Home folder on Mac HD.* That’s how it “shares” files with Mac HD.

fred 04-24-2006 08:12 PM

ahhh! I see now. Thanks for that explanation. I'll reread the manual with this in mind and get back if I have any further questions.

fred 04-26-2006 12:40 AM

OK, I've got another question that I can't find an answer to in the manual.

I've decided for the time being to not use a sandbox but to just make a full bootable clone and smart update that. The reason being I want a back up as well as being safe, and this suits me fine at the moment because if I'm nervous about a system update then I can just boot from my clone and if it gets destroyed, recreate it from the HD and wait till the fixed update is available.

However my question is this...

Say I do something on my HD that is catastrophic like for example I go to Terminal and mean to type in

Sudo rm -rf 'System Folder'

But I accidentally leave off the final quote mark and thus trash my System.

(I actually did this) :o anyway what I ended up doing was an achive and reinstall which worked OK and I didn't lose anything. But it took quite a few days to get all everything back in order.

Now If I had done that now, when I have a bootable complete clone, could I somehow just copy my clone back to the hard drive by using a command like erase HD and copy the clone to the HD?. Or is this not possible because as it says in the documentation "there are some System files that Apple recommends not copying" when making a bootable system copy.

Or would another way to go about it be to do a clean install and update the system to the latest version and then to drag my home folder from the cloned back up into the new 'Users' folder.

dnanian 04-26-2006 12:51 AM

Yes, you could boot from your copy and copy it right back. The files not copied are all things like temporary files and caches that either have no meaning across a boot, or can cause trouble when booting a copy from a different machines.

You could also clean install (Tiger) and use the Migration Assistant to migrate your applications and user files from your backup... there are many possibilities because of the nature of a full, bootable copy!

fred 04-26-2006 01:02 AM

Wow, that's fantastic.

If I wanted then to try the first option and just copy back my bootable full backup clone, would I (or indeed should I) reformat my HD first?

And is there any advantage to using the migration assistant to bring my files in rather than dragging the home folder back into 'Users'?

btw thanks for the speedy reply.

dnanian 04-26-2006 01:07 AM

No, if there's nothing wrong with the drive, there's no need to reformat. Just use Smart Update, and we'll put things back where they should be.

Migration Assistant would bring over your applications and the like, which you'd probably want. And it's a lot easier than dragging things over (since you wouldn't be able to be logged in when dragging things over, etc).

fred 04-26-2006 01:11 AM


Originally Posted by dnanian
Migration Assistant would bring over your applications and the like, which you'd probably want. And it's a lot easier than dragging things over (since you wouldn't be able to be logged in when dragging things over, etc).

Doh, of course, <slaps head>

All times are GMT -4. The time now is 11:33 AM.

Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2022, vBulletin Solutions, Inc.