TM backups working with external startup drive?

I understand that this new thing with repairing homedir's permissions isn't widely known.

This is the way to do it in Mojave: https://support.apple.com/en-us/HT203538

Apple's support has made me very clear, that Apple now support only macs with homefolders in startup drive. If / when permission issues arise (like to me, when migrating Mail from 10.12->10.14, I had tons of email attachments "downloading" forever, you can only fix those permissions that are on startup drive, because with Apple's undocumented and not-open-source command switch in " diskutil resetUserPermissions / `id -u` " only works in startup drive (/).

This might have something to do with SIP, APFS's secret security things or just T2.

Maybe "homedir in external" would work if external is HFS+?

Anybody have experience on this?

I just have this experience with external APFS drive (I got my mini2018 in the end of March, ordered it 30th of December, and then had 4 months of troubles and slow support from Apple.

I just stupidly assumed, that macos would at least warn me, if moving homedir to external APFS disk would cause troubles, but seems to be, that Apple doesn't see that necessary, since we are in the age of computing, where system & homedirs are always in internal soldered ssd. (A mac with more than one physical storage is an oddity these days.)

Has anybody tried ever to restore a full system (os & homedirs) to external APFS drive?

I'd say that if you haven't, the logical assumption is, that when it didn't work with High Sierra, why would they have changed it in Mojave?

You are aware that you can't even clone an internal APFS drive to external drive in Mojave's Disk Utility? You need 3rd party sofware for that, like CCC.

I've asked these things also here:

https://forums.macrumors.com/threads/restoring-system-from-tm-to-external-apfs.2195428/#post-27669599

https://forums.macrumors.com/threads/is-it-possible-to-install-mojave-and-keep-hfs.2138162/page-4#post-27670716

I posted another thread about the ssd:

https://discussions.apple.com/thread/250601924

The UID you used for the command was this regular unix ACL number like 508?

Not user UUID or File system UUID?

diskutil resetUserPermissions / `id 508`

Barney-15E wrote:

Apple's support has made me very clear, that Apple now support only macs with homefolders in startup drive.

That's what they always ever supported. There is nothing new about that. It has not changed.

Really? I thought it was supported before, since it was so common with powerMacs & macPros to have homedirs in some other internal drive, that I thought it was supported.

ecause with Apple's undocumented and not-open-source command switch in " diskutil resetUserPermissions / `id -u` " only works in startup drive (/).

Have you tried it with /Volumes/External instead of /?

I tried it. A lot.

But since the switch is undocumented, it might have already evolved. Can you somehow find out version number of a switch of a command?

These are pretty unusual times that we have had already 2 supplemental updates.

The problem with that command is that it gives so little feedback, if there's anything happening. I've had it running for 24 hours and couldn't tell if it was doing something or nothing.

Just few days ago, I tested DU's first aid to my ext ssd, when booted from int.

Waited for something like 30 hours. Reads and writes in ActMon were something like several terabytes. DU had used hours od CPU time and was in AM almost all the time "not responding".

I asked 9th of May apple support, if I want to have homedir's permissions in ext drive fixed, should "diskutil resetUserPermissions /dev/disk6/ `id -u`" work. They answered 22nd of July that they don't know, they have no documentation to offer and they only support homedir in startupdrive.

If i remember correctly, I also tried the volume number.

I don't have that homedir anymore. I removed it, because I thought it might have resulted conflicts with those homedirs created after booting from ext ssd.

I don't know how APFS really "secures" permissions, but homedirs created when booting from int and when booting from ext, had conflicting userID numbers. I noticed that that homedirs created by separate startupdrives does not see each other.

My (and supports) original assumption that the problems with my new mini were caused by permission problems caused by faulty migration from 10.12 and resulted hundreds of mails having their attachment "downloading" forever. And office2011 couldn't build "main identity", which lead to non-working dictionary/spelling.

I can boot to internal and try to run both DU first aid, if you'd be interested to see how it goes, but I'm a bit hesitant to do that diskutli command to not-startup-drive, since I fear it can mess up my still somehow working system and I just got the Mail problem fixed. Also it is not sure yeat, if the system breaks badly, can I restore from TM back to ext APFS. Also, when I still had that Mail problem, I checked what mails TM could restore from last 6 months and about 99% of mails were missing from backup.

At least I'm going to make new CCC clone to ext hdd in hfs+ and this time rememer to uncheck "ignore ownership" before cloning. Although I'm not sure how forgetting that affected the cloned homedirs.

haven't, but I have found some references on the web to people having done it. I don't have any user folders on external drives to test it out.

Has anybody tried ever to restore a full system (os & homedirs) to external APFS drive?

I am currently in the process of doing so. I finally got a drive to test it on.

Very nice!

I have run out of drives. I'm using one as secondary TM backup drive, although I'm not sure if they are fully working, since this my ext ssd seems to be so messed up. And another drive where I cloned this ext ssd startupdrive with CCC.

Let me know how it goes!

I'd say that if you haven't, the logical assumption is, that when it didn't work with High Sierra, why would they have changed it in Mojave?

I don't agree with your premise. It's not a logical assumption at all. There was much about APFS in High Sierra that was not ready. One thing, it didn't support Fusion drives (it worked, by the way--I ran the entire HS beta with an APFS Fusion drive).

APFS Fusion drives are now supported in Mojave. Things did change.

Yep, illogical in that sense that developers usually develop their software, but logical in that sense, that customer support is the most expensive part of computer seller, so it would be logical for Apple to try to dumb down things. Also, they make huge profits for selling these internal soldered ssd's and these also cause needs for buy new mac sooner.

Why else there's no fusion drive option in "new" mac mini lineup anymore? I'd say that GPU doesn't eat thermal envelope anymore than before... ;)

So what Apple is doing (for me) is that making fusion drive work with APFS & Mojave doesn't help, since they took away that option from mini.

Do you think they will ever allow external (parts of) fusion drives?

It would be so nice to use my now useless "super fast" int ssd as the faster part of fusion drive and buy some big cheapest $/GB ssd for the slower part...

All right!

I thought that "/" pointed to a dir, where command would search Users/ etc.

But the slash points to where the system (startup) is?

You just found out something that Apple's Support didn't bothered to do.

I remember trying to put there a path to external, but if I'd do it now, maybe it would work, since both int & ext are now startup drives.

How do you see that, could it be a problem or even the reason why my ext ssd is so messed up, that when I installed system to ext drive, there were users for both system in same /Users dir and those had conflicting UIDs (501 & 502)?

Would you waste some more time to check out that my new "messed up SSD" thread?

Barney-15E wrote:

That is an interesting question. I don't think it will search for the user account on the external, but perhaps. I don't know how it "finds" the home folder of the user. It may use the directory utilities to find the path. That wouldn't work on the external--no way to query it, I think.

Since you might still have this extra disk you used, can you test this out?

Wipe it clean, put there "Users" dir, boot from int, add a new user, change it's path to <ext>/Users/<user>, copy some stuff there and then try to fix permissions?

Barney-15E wrote:

I don't know much about that. If it says it is Ok in the end, it is Ok is all I can offer. APFS is too new and I'm not sure if Disk Utility has a grasp of it. Apple may have it dump out every little thing even though it isn't important, because they don't know if it is important.

Interesting lines are at the end:

Performing deferred repairs

warning: found physical extent corruption but repairs are disabled

The volume /dev/rdisk5s1 appears to be OK

File system check exit code is 0

Restoring the original state found as mounted

Finished file system repair on disk5s1 SSDhomeDir

Just checked that I DID forget to uncheck "ignore ownership" from that ssd in early April, when this "project" met "some" problems!

All this time I have run macOS with a drive, which ignores ownership?!?

What does that even mean, since I have 4 users in that drive and they can't read each others homedirs' "default" folders.

Just checked that I can read folders that are not created by OS.

So I did at least make one mistake in the beginning, but could that to tons of errors in file system...

I did format the ext ssd, installed Mojave to it again and Migrated few userdirs to it from a cloned hdd.

Now,

Disk Utility's first aid works to it, diskutil's verifyVolume works, "Apply to enclosed items" in Finder's homedir's info window does work, chflags -R nouchg ~ does work, BUT

diskutil resetUserPermissions / `id -u` is still never ending show. I let it run over 10 hours last night...

There must be something very toxic in my homedir...

Barney-15E wrote:

So, I've now completed the restore to APFS drive which worked flawlessly.

To make sure:

you restored the whole system from TM to external APFS drive and booted from that external drive?

All permissions are now set correctly. I no longer have access to the user directories inside that home folder. I can log in as the user with that home folder on the external with no problems. I can open/edit documents in the home folder without issue. All of those documents were created on another Mac with a different username and UID.

So,

if I'd make a system that could boot from internal drive and had homedirs in both internal and external drives

AND

the external would also be bootable (startup drive) and had its own homedirs,

THEN

I could repair all permissions of of homedirs of each system by just booting to that system and using UID number

IF

all UIDs would be only used once ie. no same numbers with two homedirs?

Like:

when booting from int:

user1 (homedir in int) 501

user2 (homedir in int) 502

uers3 (homedir in ext) 503

user4 (homedir in ext) 504

and when booting from ext:

user1 (homedir in ext) 505

user2 (homedir in ext) 506

?

Right now I have 501 & 502 when booting from int and same 501 & 502 when booting from ext...