Time Machine questions

Discussion in 'Mac Apps and Mac App Store' started by Cavara34, Sep 9, 2014.

  1. Cavara34 macrumors member

    Joined:
    Aug 14, 2012
    #1
    Hello,

    Two (related) questions:


    (1) I'm currently doing an initial Time Machine backup onto a new external HD. I've never use TM before, and I would like to use the external HD for both backups and also other files for which I won't have copies on my computer, such as maybe my iTunes library. I read somewhere that this works best if the drive is partitioned. Is that necessary and how is it done? Does the partition have to be done prior to starting the backup process; I'm already well into it.


    (2) If TM backs up, say, my iTunes library and then I delete iTunes from my computer, will the next incremental TM backup leave those files on the external HD or will it delete it because they're no longer on the computer? I'm guessing the answer is that it would delete it, and that's why I need to keep the TM backups somehow separate from anything else I want only to exist on the HD.


    Thanks in advance.
     
  2. Weaselboy Moderator

    Weaselboy

    Staff Member

    Joined:
    Jan 23, 2005
    Location:
    California
    #2
    1. Yes, you can store files as well as the TM backup on the external, but just realize that you then have no second copy (backup) of any of those files. It is better if you keep them on a second partition. Just let your TM backup complete then follow this to shrink the main partition and add a second partition.

    2. No it won't delete it immediately, but as the disk begins to get more and more full it will start to purge off older data and that may include your iTunes library depending on how big the library is and how long ago it was backed up. There is no way to tell how long that will be, so it is not a good idea to use this as your only storage for the library, even temporarily.
     
  3. gnasher729 macrumors P6

    gnasher729

    Joined:
    Nov 25, 2005
    #3
    Here's how to understand it: You have two disks, the one in your computer, and the Time Machine disk. Normally you think of the Time Machine disk as your backup - if the disk in your computer breaks, then you just put a new disk into your computer and restore the backup. But it could be that the disk that breaks is the Time Machine disk - normally you would then throw it away and buy a new Time Machine disk and create a new backup. But if you delete your iTunes library from your computer, it will be gone if your Time Machine disk breaks.

    If you want to free space on your computer, buy another cheap external disk, copy the iTunes library to that disk and back the disk up to your Time Machine disk.
     
  4. Cavara34, Sep 10, 2014
    Last edited: Sep 10, 2014

    Cavara34 thread starter macrumors member

    Joined:
    Aug 14, 2012
    #4

    Thank you very much for the advice. I'm now realizing I need an additional drive, but if I don't get one immediately, and opt to partition the one external drive I have, am I not going to have to erase that disk first? (I just finished the initial backup). It says "erase" and partition in your link. And if I then want to eliminate that partition after I get a new drive, will that also require me to erase and start over? (I don't know what you mean by "main" and "second" partition.) And as a temporary measure, TM will only operate on the relevant half of the partition? Will that just happen automatically?

    My computer drive is roughly 500 GB. The external drive is 4 TB, but I have no idea how to allocate space for a partition or if I can readjust the partition later without erasing everything, which would be a nightmare. Sorry if I'm not getting this, but I really can't just skip the partition, and have one folder on the external drive to mirror my internal drive, and others that don't exist on my internal drive? If I just did this temporarily and kept an eye on the space?

    Is the idea this: Time Machine never deletes anything except when it space has run out? If I have a document on my computer, TM backs it up, I then delete the original, and other backup is done, it won't delete that backup? If so, I wonder if it would be easier to manage this without the partition, though people say its recommended.

    The weird thing is that my WD drive is not even presenting as an icon on my desktop or a device in finder. All that comes up is "Time Machine Backups" like it's taken over the drive functioning completely. I thought I'd create a new folder in it and drag a couple of files in and then delete the originals to test what happens.

    The thing is, I have no desire to store multiple full backups of my computer drive for successive days (if that's what TM does). I probably just want the single most recent full backup from my internal drive, one at a time. I don't care what my computer looked like on some particular date six weeks ago, if I have a more recent backup. Is there a way to limit unnecessary backups so that I'm not wasting space?

    Clearly I haven't figured this out yet, so I really appreciate any further help. I'm definitely going to get another drive and triangulate everything somehow, but I'm trying to find a simple, temporary solution right now to save space.
     
  5. Cavara34, Sep 10, 2014
    Last edited: Sep 10, 2014

    Cavara34 thread starter macrumors member

    Joined:
    Aug 14, 2012
    #5

    Thanks, I realize I need an additional disk. What bothers me is that it doesn't seem like Time Machine lets you select and deselect folders within a drive that you want or don't want backed up?

    If you happen to have any thoughts on my last post above, I'd warmly appreciate it. Thanks.
     
  6. Weaselboy Moderator

    Weaselboy

    Staff Member

    Joined:
    Jan 23, 2005
    Location:
    California
    #6
    If you have a 500GB internal, a 1TB partition on the external for backup is more than large enough. Just follow this to resize the existing partition on the 4TB external to 1TB. Just grab the /// at the bottom like on the page I linked and drag it up until it is 1TB, then apply the change. This will not erase the backup you already did. This is what I was referring to as the "top" partition since it is at the top o the partition list in Disk Utility. From now on you can add and remove partitions below this top partition without impacting the data on the top one.

    Now follow this to add a second partition of whatever size you want below the top one we just resized. Yu can use that one for your misc. data files you want to store. Like I mentioned though, you now have "all your eggs in one basket". If these files are not n your internal drive and only stored on this external drive, and the external drive dies, they are gone forever.

    The way TM works is the first time it runs it does a full backup of the system like the one you already did. Subsequent backups will be much faster and smaller because they only backup new files or changed files since the last TM backup. So it always had a full copy of the latest data on the computer, without having to repeat the full backup each time.

    You can't stop TM from saving these "versions".... that's just how it works. What you can do if you like is go to System Preferences in the Time Machine pane and in Options exclude certain folders from backup completely. It sounds like you have plenty of external drive space, so I would just let TM do its thing and not worry about space used on the external.

    When you have the 4TB TM disk attached look in Finder under Devices and you should be able to see it. Yu may ned to click "show" next to devices. To see it on your Desktop open Finder then go to Finder preferences and see if you have it checked to show attached drives on the Desktop.

    You can just make a folder on the TM partition if you want and just drop folders in there and that will work, but it is not the best practice. It is just safer to avoid accidentally deleting things to keep TM on its own partition .

    The ideal setup for you here would be to buy a second drive and store these extra large files on there, then they would be in that disk and also on the TM disk (as long as the disk is attached when the backup occurs). TM by default excludes external disks rom backup, so when you get this new disk make sure you remove it from the excluded list in the TM options.

    You can do like you said and just delete a file and leave it only on the TM backup if you need it later, but that is a dangerous game like I said. The TM disk could start to get full and just decide to purge that file with no warning and it would be gone. Much better to keep it on its own partition or folder on the external.

    Hope this helps.
     
  7. Cavara34 thread starter macrumors member

    Joined:
    Aug 14, 2012
    #7

    Okay, great. Thanks for your time.
     
  8. Cavara34 thread starter macrumors member

    Joined:
    Aug 14, 2012
    #8

    Unfortunately, unlike in the screenshot of the link you provided, it doesn't say "this drive will not be erased" for me. It indicates that it will be if I try to partition it.
     
  9. Weaselboy Moderator

    Weaselboy

    Staff Member

    Joined:
    Jan 23, 2005
    Location:
    California
    #9
    Does it show that /// at the bottom where you can just drag it up? You don't to use that drop down that makes two partitions. You want to just resize the existing one by moving that /// up.
     
  10. Cavara34 thread starter macrumors member

    Joined:
    Aug 14, 2012
    #10
    Okay, got it. Thanks again. It's been a great help.
     
  11. ItWasNotMe macrumors regular

    Joined:
    Dec 1, 2012
    #11
    Go to System Preferences ; Time machine.

    Bottom Right is button labelled 'Options...' - click this

    Gives you window titled 'Exclude from backups'

    1. To exclude additional items
    a. Click the + button
    b. Gives 'Finder-like' window'
    c. Navigate to the item you want to exclude
    d. Click the 'Exclude button (bottom right)
    e. Repeat a -> d until you have excluded everything you don't want backed up
    2. If something is excluded and you want it backed up
    a. Highlight the item on the 'Exclude from backups' window
    b. Click the - button

    Items 1 and 2 can be at drive/folder/file level as you choose.

    When you have finished all this; click the 'Save' button. A two minute timer will then run down and Time machine will start the next backup.
     

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