I'm just wondering: if I'd make a bootable clone (on an ext disk) would the T2 security have to be set at 'no security' (or whaterver the lowest settings is called) to actually allow a boot from clone? If so, I'd have to have this as default T2 settings as one doesn't know in advance when one needs to start up from an external clone (in the future), no?
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T2 & ext disk clone boot [Resolved]
- Thread starter strawbale
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I use Bombich’s Carbon Copy Cloner, which has published this article with two sections on T2: https://bombich.com/kb/ccc5/help-my-clone-wont-boot
The article answers your question and tells you how to enable an external boot.
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Assuming SuperDuper! deals with T2 in a similar way?
PS: just saw that CCC has paid updates whereas it seems SD! updates are free?
PS: just saw that CCC has paid updates whereas it seems SD! updates are free?
Time Machine requires HFS+. Backups cannot be stored on APFS disks.
I've rebooted to a Superduper backup on an external drive (a Samsung T5) without issue. As expected, I did have to set the Startup Security Utility to allow booting from an external drive. The author of Superduper recommends that the external drive be formatted with APFS.
I've been using Superduper since 2012 and I've never been asked to pay a fee for an update.
Does that mean I can't have a SD! clone partition and TM backup partition on the same external disk?
Well TM requires HFS+ : #7
That means i need to reconsider my planning and maybe have (a) separate clone disk(s).
You should be able to add an HFS+ volume to the APFS disk, but I'd strongly advise putting two backups on the same disk. If that disk fails you lose two backups at once.
strawbale asked:
"Does that mean I can't have a SD! clone partition and TM backup partition on the same external disk?"
Even if you can do this, you don't really want to.
Because -- if for some reason you "lose that drive", you've lost BOTH backups!
Better to keep your TM backup on a drive that is dedicated ONLY to TM, and use another drive for your bootable cloned backup.
Things will just work out better that way...
"Does that mean I can't have a SD! clone partition and TM backup partition on the same external disk?"
Even if you can do this, you don't really want to.
Because -- if for some reason you "lose that drive", you've lost BOTH backups!
Better to keep your TM backup on a drive that is dedicated ONLY to TM, and use another drive for your bootable cloned backup.
Things will just work out better that way...
I wasn't planning on having just one backup drive - I'd hoped to get away with 2 drives: drive A (on site) with a TM backup partition and a CC/SD! clone partition and drive B (off-site) with a TM backup partition and a CCC/SD! clone partition.
If I'd have to keep TM backups and CCC/SD! clones on separate disks ànd have on-site and off-site versions I'd need 4 disks...
How do other people do this?
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see: #14strawbale asked:
"Does that mean I can't have a SD! clone partition and TM backup partition on the same external disk?"
Even if you can do this, you don't really want to.
Because -- if for some reason you "lose that drive", you've lost BOTH backups!
Better to keep your TM backup on a drive that is dedicated ONLY to TM, and use another drive for your bootable cloned backup.
Things will just work out better that way...
I set the Startup Security Utility to allow booting from an external drive.
I use one external 4TB drive partitioned into a 3TB partition for TM and a 1TB partition for a bootable CCC daily clone.
TM partition is formatted HFS+ Journaled, CCC partition is formatted APFS. It works fine.
If the drive fails I could have another one in place in less than an hour. I also keep backups on my NAS.
I use one external 4TB drive partitioned into a 3TB partition for TM and a 1TB partition for a bootable CCC daily clone.
TM partition is formatted HFS+ Journaled, CCC partition is formatted APFS. It works fine.
If the drive fails I could have another one in place in less than an hour. I also keep backups on my NAS.
Dr. Stealth, thanks again for sharing your valuable experience!
I know now that I can go ahead with my original plan.
Next question:
How do I format and partition a (new) external disk to be used for one (or two?) clone(s) and TM backups:
Partition 1 APFS (for Mojave clone)
Partition 2 APFS (for 10.15 clone)* ?
Partition 3 HFS+ (for TM backups)
*) SuperDuper! support wrote me: "Well, you can have the two APFS volumes in one container, but depending on the number of volumes there, they may not be bootable: APFS has more restrictions about needing to be the first partition (etc)."
How do I format and partition a (new) external disk to be used for one (or two?) clone(s) and TM backups:
Partition 1 APFS (for Mojave clone)
Partition 2 APFS (for 10.15 clone)* ?
Partition 3 HFS+ (for TM backups)
*) SuperDuper! support wrote me: "Well, you can have the two APFS volumes in one container, but depending on the number of volumes there, they may not be bootable: APFS has more restrictions about needing to be the first partition (etc)."
"How do I format and partition a (new) external disk to be used for one (or two?) clone(s) and TM backups:
Partition 1 APFS (for Mojave clone)
Partition 2 APFS (for 10.15 clone)* ?
Partition 3 HFS+ (for TM backups)"
Well, you might consider making ALL THREE partitions HFS+.
Mojave should still boot and run from an HFS+ external drive (I do it).
As for 10.15 -- who knows? A little early to be worrying about that!
Partition 1 APFS (for Mojave clone)
Partition 2 APFS (for 10.15 clone)* ?
Partition 3 HFS+ (for TM backups)"
Well, you might consider making ALL THREE partitions HFS+.
Mojave should still boot and run from an HFS+ external drive (I do it).
As for 10.15 -- who knows? A little early to be worrying about that!
I formatted two APFS (clone) partitions and a HFS+ TM partition.
Put a SD! clone on one APFS partition and a full TM backup on the HFS+ partition.
Managed to allow booting from an external disk, with some trouble though - see https://forums.macrumors.com/threads/how-to-allow-start-up-from-ext-disk-resolved.2158249/
Booted from the SD! clone and worked fine.
PS: I kept the security setting at 'Full Security' as suggested here (thank you F-Train for the link): https://bombich.com/kb/ccc5/help-my-clone-wont-boot
Put a SD! clone on one APFS partition and a full TM backup on the HFS+ partition.
Managed to allow booting from an external disk, with some trouble though - see https://forums.macrumors.com/threads/how-to-allow-start-up-from-ext-disk-resolved.2158249/
Booted from the SD! clone and worked fine.
PS: I kept the security setting at 'Full Security' as suggested here (thank you F-Train for the link): https://bombich.com/kb/ccc5/help-my-clone-wont-boot
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