I'm trying to use Time machine for the first time but it wants to format to a a read only with new MBP Mojavie and then I cannot use the passport for other things. I reformatted to OS journaled but now Time machine won't back it up unless I erase and make it a APFS. How can I have both Time Machine and other items on this external HD?
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Time machine a read only with new MBP Mojavie
- Thread starter brobson
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If there is adequate space on the drive, you could add an additional APFS volume on the disk (or some other format, such as HFS+ or exFAT).
If you do this, you should leave the TM volume larger than what you expect to back up so there is plenty of space for history/versions of data.
If you do this, you should leave the TM volume larger than what you expect to back up so there is plenty of space for history/versions of data.
A couple things to consider.
Typically I would like the backup space to be at least double the space. So, if the Mac getting backed up has a 500GB SSD, I would want the minimum space available to be 1TB.
The more history you want, the more space you need. The above is a guess, as most folks won't fill their drive completely...so, let's say you had a 500GB internal drive, and you fill it 60%....so you have something like 300GB to back up. 1TB would be adequate for all the data plus some history.
Reminder: Time Machine keeps making backups, and retains older versions (history) until the drive/volume is full. Once close to full, TM automatically deletes history so there is enough space to get the most recent versions of files backed up. So:
More space = more history.
The other thing to consider is how much non-TM space you need for manual archives or other storage. Let's say you need 1TB of space for manually managed storage. You could do:
1.5TB for storage (extra room for overhead...and never fill a drive 100%)
3.5TB for TM (the remainder of the drive)
Typically I would like the backup space to be at least double the space. So, if the Mac getting backed up has a 500GB SSD, I would want the minimum space available to be 1TB.
The more history you want, the more space you need. The above is a guess, as most folks won't fill their drive completely...so, let's say you had a 500GB internal drive, and you fill it 60%....so you have something like 300GB to back up. 1TB would be adequate for all the data plus some history.
Reminder: Time Machine keeps making backups, and retains older versions (history) until the drive/volume is full. Once close to full, TM automatically deletes history so there is enough space to get the most recent versions of files backed up. So:
More space = more history.
The other thing to consider is how much non-TM space you need for manual archives or other storage. Let's say you need 1TB of space for manually managed storage. You could do:
1.5TB for storage (extra room for overhead...and never fill a drive 100%)
3.5TB for TM (the remainder of the drive)
Another point to consider:
While the default in TM is to backup everything, some folks only backup their user directory (all the data, files, browser history, bookmarks, etc., within a user home folder.)
While it is convenient to back up the OS, it uses a lot of TM space, and OSes can be reinstalled, along with applications. User stuff is typically unique and precious data that should always be backed up. So if space is an issue, prioritize the user home folder over any system files when doing TM (or any other type of backup software) backups.
While the default in TM is to backup everything, some folks only backup their user directory (all the data, files, browser history, bookmarks, etc., within a user home folder.)
While it is convenient to back up the OS, it uses a lot of TM space, and OSes can be reinstalled, along with applications. User stuff is typically unique and precious data that should always be backed up. So if space is an issue, prioritize the user home folder over any system files when doing TM (or any other type of backup software) backups.