Thank you both for this information. Unfortunately I am not in a position to buy another external HD so I will have to manage with what I have. In reading through your comments, I realized that there's no need for the iTunes backup to be in a separate partition (at least, I think this is so); I have no idea why I set things up that way originally. (I continue to refer to "iTunes" even though it's not called that anymore...one cannot usually teach old dogs new tricks.) Here's what I think I'll do, subject to your better advice:
1. Reformat the backup drive to APFS without a partition 2. Set up Time Machine to back up the main HD to the newly-formatted external HD 3. Copy the contents of the current iTunes drive to the newly-formatted backup drive. 4. Reformat the current iTunes drive to the new format 5. Copy the backed-up iTunes material back to the newly-reformatted external iTunes drive 6. Set up Time Machine to back up the external iTunes drive to the newly-formatted external HD Will this approach work? Or, what do I need to change in that proposal? Again, my thanks for your input. Bill On Friday, January 1, 2021 at 9:39:07 PM UTC-5 Centrisman wrote: > I hope these two articles from Seagate and Apple helps. BTW, TM is for > backups not archiving. > > Formatting a drive to be used with Time Machine: > > macOS requires that a drive be formatted with a specific file system to be > used with Time Machine > > - For Big Sur use Apple File System (APFS) when setting up a new backup > - For macOS versions for 10.6 (Snow Leopard) to 10.15 (Catalina) use > Mac OS Extended (Journaled) also referred to as HFS+ when setting up a new > backup > > Backup disks you can use with Time Machine > > Time Machine can back up certain external storage devices connected to > your Mac or available on your network. > > To use Time Machine to make a backup of your Mac, you need one of these > types of storage devices: > > - External USB, Thunderbolt, or FireWire drive connected to your Mac > > <https://support.apple.com/en-us/HT202784?displayMode=headless&src=support_app#drive> > - Network-attached storage (NAS) device that supports Time Machine > over SMB > > <https://support.apple.com/en-us/HT202784?displayMode=headless&src=support_app#nas> > - Mac shared as a Time Machine backup destination > > <https://support.apple.com/en-us/HT202784?displayMode=headless&src=support_app#mac> > - External drive connected to an AirPort Extreme Base Station > (802.11ac) or AirPort Time Capsule > > <https://support.apple.com/en-us/HT202784?displayMode=headless&src=support_app#router> > - AirPort Time Capsule > > <https://support.apple.com/en-us/HT202784?displayMode=headless&src=support_app#airport> > > ------------------------------ > External drive connected to your Mac > > Time Machine can back up to an external drive connected to a USB, > Thunderbolt, or FireWire port on your Mac. If the disk isn't using the > correct format, Time Machine will prompt you to erase it. > ------------------------------ > Network-attached storage (NAS) device that supports Time Machine over SMB > > Many third-party NAS devices support Time Machine over SMB. For details, > check the documentation for your NAS device. > ------------------------------ > Mac shared as a Time Machine backup destination > > To use another Mac on your network as a Time Machine backup destination, > complete these steps on the other Mac: > > 1. Choose Apple menu > System Preferences, then click Sharing. > 2. From the list of services on the left, select File Sharing. > 3. From the Shared Folders list on the right, click the add button > (+), then choose a folder to use for Time Machine backups. > 4. Control-click the folder that you added, then choose Advanced > Options from the shortcuts menu that appears. > [image: macOS Sharing System Preferences Shared Folders options] > 5. From the Advanced Options dialog, select “Share as a Time Machine > backup destination.” > > When setting up Time Machine on your other Mac computers, you should now > be able to select the shared folder as a backup disk. > ------------------------------ > External drive connected to an AirPort Extreme Base Station (802.11ac) or > AirPort Time Capsule > > Time Machine can back up to an external USB drive connected to an AirPort > Extreme Base Station (802.11ac model) or AirPort Time Capsule. > > 1. Connect the drive directly to your Mac, then use Disk Utility to > erase it > > <https://support.apple.com/guide/disk-utility/erase-and-reformat-a-storage-device-dskutl14079/mac> > . > 2. Connect the drive to a USB port on your AirPort base station, then > turn it on. > 3. Open AirPort Utility, then select your base station and click Edit > to view its settings. > 4. Click the Disks tab in the settings window. > 5. Select your backup disk from the list of partitions, then select > “Enable file sharing”: > [image: AirPort Utility window Disks tab with "Enable file sharing" > turned on] > 6. If more than one user on your network will back up to this disk > with Time Machine, you can use the Secure Shared Disks pop-up menu to make > sure that they can view only their own backups, not yours. Choose “With > accounts” from the menu, then click the add button (+) to add users. > 7. Click Update to restart your base station and apply the settings. > > ------------------------------ > AirPort Time Capsule > > Time Machine can back up to the built-in hard disk of an AirPort Time > Capsule on your network. > > > ------------------------------ > Learn more > > - How to back up your Mac with Time Machine > <https://support.apple.com/kb/HT201250> > - Time Machine can't back up to a disk formatted for Windows, or to an > iPhone, iPad, or iPod touch. > > Published Date: November 12, 2020 > > On Fri, Jan 1, 2021 at 4:59 PM Bruce Johnson <joh...@pharmacy.arizona.edu> > wrote: > >> On Jan 1, 2021, at 12:57 PM, William Spencer <wspen...@gmail.com> wrote: >> >> >> Hi there: I’ve got Big Sur installed now, and I’m hoping to be able to >> use Time Machine to do my backing up rather than Carbon Copy Cloner, which >> is what I’ve been using for quite a while now. But I can’t see how to >> configure TM to do what I need. Here’s the setup: >> >> - I have three physical HDs, one internal to the Mini and two >> external. >> - One of the externals is partitioned, so the system actually thinks >> I have four HDs. >> - The idea is to back up the internal to one partition and the >> standalone external to the other partition. >> >> Time Machine is a real ‘fire and forget’ backup system…you turn it on >> and you don’t have to fuss with it ever again. >> >> Time machine backs up the booted volume (plus any mounted external >> volume, optionally, see link below) >> >> IS the standalone external another bootable drive? Then, unfortunately >> what I would do is back it up with CCC (or it’s own Time Machine >> Configuration while booted) That way you can do the back up internal to one >> partition, the external to another. and be able to recover them both as >> bootable drives; you cannot use a bootable volume backed up as a mounted >> external drive in Migration Assistant (which is how you restore an entire >> volume from Time Machine) >> >> >> - TM isn’t showing me one of the (partitioned) HDs as a possible >> destination for a backup. >> >> Likely it is because it’s not the correct format (see below) >> >> >> - It also isn’t showing me the internal HD as a source. >> >> You don’t select a source in Time Machine. It backs up the currently >> booted volume. By default it excludes external drives but you can undo that >> in the preferences: >> https://www.macworld.com/article/3153995/how-to-make-sure-time-machine-backs-up-external-drives.html >> (you >> can also exclude items on the boot drive that way as well. My email >> folders, for example are excluded, because all my email “lives” on the >> server, so restoring my email is merely a matter gdropping the account, >> re-adding it and re-synching the folders. >> >> This doesn’t work if you use POP or have local non-synched folder (they >> show as ‘On my Mac’ in the list in Mail) >> >> >> - The two it's showing (which are for what used to be called iTunes, >> one the source and the other the destination) are formatted as Mac OS >> Extended (Journaled); the two it isn’t showing (for the HD itself, ditto) >> are formatted as APFS. >> >> >> I”m not sure why, Big Sur is supposed to use APFS fro Time Machine, at >> least per the Ars Techhnica Big Review: >> https://arstechnica.com/gadgets/2020/11/macos-11-0-big-sur-the-ars-technica-review/9/#h1 >> >> >> >> - Is that difference in format a (or the) issue? >> - If I reformat anything I will lose all that data, as you know. >> - How can I proceed? >> >> Honestly, what I would do is purchase a new larger external HDD (mine is >> a 4TB one I got at Costco for ~$80-$90 I think, on sale) and set it up as >> one or two time machine volumes. (depending on why you want those two >> drives backed up to different partitions) >> >> Time Machine is a multi-point backup/restore system (It’s been a very >> long time since I've used CCC for this purpose) It maintains a database of >> changed files and folders and only backs up the changes as it goes. So you >> want to have (imo) at a minimum 2X your backed up data as free space, 3X is >> closer to optimal. >> >> So I’d look at how much you have to back up to start, and size it from >> there. >> >> -- >> Bruce Johnson >> University of Arizona >> College of Pharmacy >> Information Technology Group >> >> Institutions do not have opinions, merely customs >> >> >> -- >> You received this message because you are a member of the iMac Group, a >> group for those using Apple iMacs and eMacs. >> The list FAQ is at http://lowendmac.com/imac/list.shtml and our >> netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml >> To post to this group, send email to imac...@googlegroups.com >> To leave this group, send email to imaclist+u...@googlegroups.com >> For more options, visit this group at >> http://groups.google.com/group/imaclist >> >> --- >> You received this message because you are subscribed to the Google Groups >> "iMac Group" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to imaclist+u...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/imaclist/6C7DDF10-3960-430E-87F2-F1C10A4F8FB8%40pharmacy.arizona.edu >> >> <https://groups.google.com/d/msgid/imaclist/6C7DDF10-3960-430E-87F2-F1C10A4F8FB8%40pharmacy.arizona.edu?utm_medium=email&utm_source=footer> >> . >> > -- You received this message because you are a member of the iMac Group, a group for those using Apple iMacs and eMacs. 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