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sidetracked
04-16-2006, 09:25 PM
Forgive what might be a dumb question, but I'll admit it, I'm less than a computer wiz...

Should the 'Ignore Ownership on This Volume' box be selected on my external HD that I'm using for a bootable back-up? I read one article (MacWorld 7/04) that seemed to imply it was crucial that box be checked to not run into problems if trying to boot from the back-up.

But reading answers here, it seems like your recommendation is not to check that box. Indeed the implication was that checking that box could cause problems, not solve them.

Before reading the article, I did a back-up with the box not checked, and it seemed to work fine (I was able to boot from it).

But for future, what's the best way to go?

(By the way, SuperDuper has been amazingly easy to use so far. I'm telling all my other old, luddite friends).

dnanian
04-16-2006, 11:20 PM
Ignore Ownership should always be unchecked (unchecked = ownership on). I don't think that Macworld article meant to say "checked", since a boot volume always has ownership on...

Don't check the box unless you have a really good reason to do so. (SuperDuper! will always uncheck it before copying to/from a volume.)

Hope that helps -- and I'm glad you've found SD! easy to use!

fred
04-24-2006, 12:24 AM
Ignore Ownership should always be unchecked (unchecked = ownership on). I don't think that Macworld article meant to say "checked", since a boot volume always has ownership on...

Don't check the box unless you have a really good reason to do so. (SuperDuper! will always uncheck it before copying to/from a volume.)

Hope that helps -- and I'm glad you've found SD! easy to use!

Hi I just got super duper yesterday and I'm really happy with it. However it took me a long time to get the volumes on my new external hd to show up because I didn't know that one had to log in as a registered user and not as a guest. The reason I'm telling you this is that during my investigations to make it work I looked at the permissions.

My La Cie hd was already *defaulted* to 'ignore permissions' checked which is what I thought I wanted, and to be extra sure I changed the permissions so that I was the 'Owner and the 'Group' and all three permissions groups were set to read/write on all volumes

I've just left it like that with 'ignore permissions' checked as that is what it always was, and seeing as it is checked it became irrelevant that I changed the permissions. Then I came across this thread which is telling me to uncheck the box and use permissions.

So...

My question is basically two part...(I) what are the reasons for unchecking and using permissions and (II) how should the permissions be set.

I've made a bootable clone of my complete hd on one of the partitions, I'm not booting from this clone at the moment (I'll post another thread with questions about this soon) I'm just using Smart Update to keep it up to date, until I make a decision on whether to use the sandbox feature. I've also got another mac connected via an ethernet/router that is using a different volume on the hd to store files so that person needs to access their volume.

Everything is working fine at the moment so I'm wondering what is going to be different if I uncheck the 'ignore permissions' checkbox and how should the permsissions be set?

dnanian
04-24-2006, 09:49 AM
It sounds to me like you're using SuperDuper! to back up over a network (since you can't really log into a computer as "guest" directly). If you're storing the backup on a drive inside an image, the permission setting for that drive doesn't really matter, since the image itself with have permissions ON (unchecked).

It's critical to use Permissions in general when trying to make a backup. The reason why is simple: every file and folder on the system has ownership and permission information. Checking the box (turning ownership off) makes the system ignore that information, which also makes it impossible to save and restore properly.

fred
04-24-2006, 10:08 AM
It sounds to me like you're using SuperDuper! to back up over a network (since you can't really log into a computer as "guest" directly). If you're storing the backup on a drive inside an image, the permission setting for that drive doesn't really matter, since the image itself with have permissions ON (unchecked).

It's critical to use Permissions in general when trying to make a backup. The reason why is simple: every file and folder on the system has ownership and permission information. Checking the box (turning ownership off) makes the system ignore that information, which also makes it impossible to save and restore properly.

The clone I made was just to a normal firewire drive which worked perfectly. I didn't even notice the checkbox at that stage. I had just bought the hd and I made three partitions on it. One for the backup of my hd and one for my own archive and another to be used as storage space for another computer on my ethernet network. It was only when I was trying to get the other computer to be able to use their partitions that the permissions thing came up. I didn't realise that they had to log in with my name and password to see the volume I had reserved for them. Before I discovered this I thought it was a permissions issue.

Anyway before I made the clone I had noticed that the permissions checkbox was checked by default. The clone was made with this on. I have checked the clone and everything is fine. All the permissions on the clone are correct and the same as the hd. The 'ignore permissions' was checked when I cloned the hd and they are still checked now, but all the permisssions are fine.

The only reason I'm writing right now is because of this thread which warns against having that box checked, not because there is a problem. :)

So I'm a bit confused about it. I repeat there is no current problem and it was cloned with the 'ignore permissions' box checked and it is still checked. What is supposed to go wrong?

dnanian
04-24-2006, 10:14 AM
SuperDuper! won't let you make a copy with the checkbox checked: we'll uncheck it automatically. Are you sure it was checked after the copy was complete, and you were copying directly to the backup?

If so, I can't see how the ownership/permissions could be fine...

fred
04-24-2006, 10:32 AM
Well you know, it's very rare that I'll say 100% in any circumstances. It's your software so you know more than me and if you say that it is *impossible* then I will accept that. But I'm as near as dammit to 100% that the box was checked.

The reason I say this is that I didn't even notice that checkbox before because it only ever appeared when I connected my new drive. And when I was making inquiries on another thread purely to do with getting the volume to show up on a networked computer I was advised to check that box. When I had a look at it, it was then I first noticed it and I also noticed that it was already checked, as I couldn't check it I nevertheless changed the permissions on *all* the volumes to be that I was the owner and also the group and I changed the permsissions for the owner, group and others to be 'read/write'.

I've just had another look at the backup volume and the box is unchecked and the permissions are changed back to the same as my hd. So I guess that super duper must have turned the checkbox off and altered all the permissions to be correct. I was just looking at the other volumes and not the back up volume and I know it was checked when I went to clone but as I said SD must have corrected it first.

dnanian
04-24-2006, 10:37 AM
Yes, by default an external drive -- when it first gets attached to a system -- usually has its box checked. This is because Apple anticipated that a user would bring a drive to a different system, and -- since the files might be owned by a different user than the one who connected the drive -- they should make them accessible by default.

Backups, on the other hand, are different. We're not trying to make the files "accessible to foreign systems", we're trying to make them exactly the same as the source. Without ownership on*(unchecked), that's not possible to do.