Space needed for Time Machine backups?

I have a 160 gb macbook pro and am wondering how much space I would need on an external hard drive if I plan on backing up with Time Machine. I bought a 500 gb drive already, but would also like to use it for backing up a pc computer and don't know if I have enough space for both. Any advice would be appreciated!

In addition to Bob's advice, note that you should partition the drive, so Time Machine has it's own, exclusive space.
See #5 in [Time Machine - Frequently Asked Questions|http://web.me.com/pondini/Time_Machine/FAQ.html] (or use the link in *User Tips* at the top of the +Time Machine+ forum) for formatting instructions.
You'll have to figure out what Format to apply to the second partition for the PC backups, probably either MS-DOTS(FAT) or ExFAT.

Similar Messages

  • Size of hard disk for needed for Time Machine backups

    How does one determine what size of hard disk one should buy for one´s backups?
    My MacBookPro´s built-in hard disk has a capacity of apprx 190GB. Does time machine back up EVERYTHING on one´s hard disk (i.e, documents, applications, operatimg program, settings, boot sectors etc. (at the moment I only have one partition and no WINDOWS loaded)

    Does time machine have the capacity to back up (and then restore) EVERYTHING on one´s hard disk (i.e, documents, applications, operatimg program, settings, boot sectors etc. (at the moment I only have one partition and no WINDOWS loaded)?

  • How big an external hard drive do I need for Time Machine backups?

    I run a 2 Ghz iMac with 1Gb memory, currently using around 108 GB of the 150 GB available memory.
    Hpw larghe an external hard drive do I need to run Time Machione efficiently? 500GB? 320? 520?

    Not answered - don't know why!

  • Need a external HD 40% bigger than internal for Time Machine backups??

    I've heard that using Time Machine as my backup program I need a hard drive that's about 40% bigger than the source (internal) hard drive I want to backup. Some in these forums have said I need a external HD 2x or 3x as big as the internal hard drive for Time Machine backups!
    What's your general rule, and does Apple recommend a certain percentage increase of the target over the source hard drive?

    There is no set rule, except that the drive being used for Time Machine must be at least as large as the data (not drive) being backed up.
    So if you have an internal 500GB drive, but you only have 300GB full, and with exclusions (things that you select NOT to back up), only 200GB needs to be backed up, then a 320GB external drive could do an adequate job (even though the internal drive is 500GB).
    During the first backup, Time Machine will back up everything (that is everything you have set it to backup). So the external drive volume used for the backup must be at least the size of the data being backed up. After that, Time Machine creates an incremental backup states every hour, for things that changed during that hour. But because it is Time Machine and not just Backup Machine, the previous versions of the files that changed are also retained. Therefore, over time, the Time Machine backup archive will take up more and more space.
    Once you run out of space, Time Machine will tell you and start deleting the oldest backup states to make room for the newest states. So if you have a really huge volume for your Time Machine backup, you can +go back in time+ further (probably back to the date you started using Time Machine) than if you have an adequate but smaller size drive for that purpose.

  • Can you use the same external hard drive for Time Machine backups and as an additional storage drive?

    I have an external HD that I've been using exclusively for Time Machine backups. I need to clear space on my hard drive, so I was thinking to move music & photos to an external drive.  Wondering if I can use the same one I have (which I'll aslo keep using for Time Machine) or if I need to get another drive. 

    Hi Jossydtaylor,
    Time Machine can use either an entire external disk or a partition of that disk:
    OS X Mountain Lion: Disks you can use with Time Machine
    http://support.apple.com/kb/PH11171
    You can use Time Machine with a Time Capsule, and with USB, FireWire, and Thunderbolt disks. The backup disk can be directly connected to your computer or be on a network. If the backup disk has been divided into partitions, you can use one of the partitions.
    If the disk is partitioned using the Master Boot Record (MBR) partition type, some partitions may not be available for use with Time Machine. The GUID Partition Table (GPT) partition type is recommended.
    For more info on partitioning, see this article:
    Disk Utility 12.x: Partition a disk
    http://support.apple.com/kb/PH5845
    Cheers!
    - Ari

  • I am trying to install Mavericks on my McbookAir, but it won't install, saying that my hd is used for time machine backups. I have an external HD connected to my mbAir that I'm using for time machine.

    2012 Macbk air, with OSX 10.8.5. See my question above. Mavericks won't install on my Air's HD, says that both the HD - AND - the external HD (which has a different name from the laptop HD) are used for time machine backups. I've deleted my time machine plists, restarted, repaired permissions, turned time machine off, repeatedly selected the external drive in time machine preferences. HELP. (Install went perfectly on my desktop Mac, which also has an external HD for time machine).

    I need to add that the only place I have the "Backups.backupdb" folder is on my backup external disk, and it's not on my HD    :-(    . If it were, I'd delete it!

  • Can two macs use same disk for Time Machine backup with Airport Extreme?

    Hi
    I use a Western Digital disk as a wireless Time Machine backup connected to the USB port on my Airport Extreme and it works great. My question is: can my girlfriend use that same disk for Time Machine backup from HER computer too? (I don't mind formatting the disk if needed.)
    If she can't, is it then possible to connect a USB hub and have two disks hooked up to the Airport Extreme?
    Thanks for helping. I am constantly in awe of all the help people like you give people like me. Thanks!!!
    Jakob

    I've gone through the manual setup and the assisted setup and can't seem to get my MacBook to use the Time Machine. Any thoughts or help would be greatly appreciated.
    Well, as the Jolly Giant points out....+this type of configuration is not supported by Apple+, so it's difficult, if not impossible, to provide a fix for something that Apple says that you cannot do. Reference these Apple Support documents regarding this topic:
    http://support.apple.com/kb/HT2038
    http://docs.info.apple.com/article.html?path=Mac/10.6/en/15139.html
    Your situation is not unlike other users who try this and find that one computer may backup...(usually for a limited time before corruption issues start to creep in)...but another computer cannot backup. Count me as one of those users who thought that because things seemed to work that I had somehow "beat the system".
    I started getting the corruption error messages after 4-5 weeks of successful backups, so I figured that it did not make sense to continue to try to get a second computer to backup (yes, I too could not setup a second Mac to backup).
    Sorry, I could not get a second machine to backup, so can't tell you how to accomplish that goal. If you want to continue to try backing up this way, you might want to also think about a second backup strategy...just in case backups become corrupted on the WD drive.
    Maybe if Apple says you cannot do this, they just may be right?
    Message was edited by: Bob Timmons

  • Is it possible to use more than one external hard drive for Time Machine backups?

    I want to use two hard drives for Time Machine backups.
    Bigger one keep at home and be sure it is safe.
    Second one (very small pocket size) keep with me for travels.
    I want to backup to both drives to be sure I can restore everywhere and to be sure if something bad happened with my small travel disk I can restore from home backup.
    Is there any problem with listed schema? Is it normal for Time Machine to handle backups for different drivers and keep everything consistent and smooth?

    I really need some help!  I have been using an Iomega NAS 1TB HD for the past year.  And I received an error message.  I believe I have ran out of memory on this drive.
    Then recently in the last couple of months I got a ReadyNAS Duo 2TB with 2TB RAID.  Should I switch my back ups to this one and delete the other back up file or keep the old back up image file on the Iomega?
    Can I transfer the old image back up to this new ReadyNAS? How do I do this?
    I appreciate any help.

  • Can I select certain drives only for Time Machine backup?

    I have several internal drives and several external drives connected to my MacPro desktop computer.  If I backup everything in all of the drives using Time Machine, the capacity on my designated external drive for Time Machine backup will soon be filled.  Is there any way to selectively backup via Time Machine from  only designated drives, not all drives connected (internally or externally) to my computer?  Is so, how can that be done?  I assume that Time Machine will start deleting data when its capacity is exceeded.  If that is so, and I remove the designated Time Machine drive at that point and replace it with a new drive, will the removed drive thereafter be able to be reinserted and the prior material read and transferred as needed? Is there any way to utilized Time Machine after I insert the replacement drive to only archive new material saved after the switch of drives?

    Yes, mount the drive by opening a new Finder window and clicking on your base station's name in the left column that says 'Shared'. Then double click on the drive name to mount it on your desktop. From there, open Time Machine prefs and select that mounted drive as your backup disk. Time machine will then back up to it. Theoretically.
    If you want that disk to automatically mount every time you login to your computer, go to Sys Prefs Panel and select 'Accounts'. Then click 'Startup Items'. From there, drag the mounted drive's icon from the desktop in to that startup items list. It will then auto-mount from there forward.
    I have had many problems backing up this way with Time Machine. It will, 9 times out of 10, fail over a wireless backup with an Airport Extreme Gigabit base station and a 1TB Western Digital My Book. Nothing seems to fix, so I have given up. When TM is finally fixed - I will use it. Until then, it's junk software as far as I'm concerned.
    But - best of luck. The instructions above are how it's 'supposed' to work..

  • Can I partition a hard drive so that one partition is for windows files and the other is for time machine backups?

    I have a 1TB WD passport that currently contains windows files e.g photos, documents, etc. Can I partition it so that one partition contains these files and the other partition is used for time machine backups? Also, how do I change the partition system on the hard drive so that it uses the GUID partition system?
    Thanks in advance.

    Yes, you can, though you need to format and partition the drive from the scratch.
    1) back up your PC data on other drive.
    2) partitioning your drive into 2 partitions with Disk Utility.
    3) format one partition by Mac OS extended (journaling) for Time Machine, the other by exFAT for PC data.
    4) restore PC data on exFAT partitioned drive.

  • HT201250 How do I find out what portable drive was the drive I used for Time Machine Backup?

    Hi, I have 10.7.4 and need to figure out what drive I was using for Time Machine Backup.  I have three drives and I have connected each of them to my macbook pro, but I get an error, "Time Machine Error, The backup disk is not available" when I hit the time machine icon on the top of the screen and the "backup delayed" prompt.  If I try Back up Now I get message, "Time Machine could not complete the backup.  Back up disk is not available."  I am trying to figure out what the time machine back up would actually look like as a file on the drives but I don't see a folder/file name Time Machine.  If I enter Time Machine I can see in the far right column, in purple, the last back up date (Sept. 12, 2012), but when I hit it nothing happens.  In the Time Machine preference box the select disk has, in red and to the right, "Delayed" with an "i" within a circle, and the option indicates, "Next backup: when disk is connected."
    I know I have a years worth of backups on one of the three drives, but I can't figure out how the heck to find them or how to determine what was the last drive I used for the backups within Time Machine.  Help please.

    Hi, I have 10.7.4 and need to figure out what drive I was using for Time Machine Backup.  I have three drives and I have connected each of them to my macbook pro, but I get an error, "Time Machine Error, The backup disk is not available" when I hit the time machine icon on the top of the screen and the "backup delayed" prompt.  If I try Back up Now I get message, "Time Machine could not complete the backup.  Back up disk is not available."  I am trying to figure out what the time machine back up would actually look like as a file on the drives but I don't see a folder/file name Time Machine.  If I enter Time Machine I can see in the far right column, in purple, the last back up date (Sept. 12, 2012), but when I hit it nothing happens.  In the Time Machine preference box the select disk has, in red and to the right, "Delayed" with an "i" within a circle, and the option indicates, "Next backup: when disk is connected."
    I know I have a years worth of backups on one of the three drives, but I can't figure out how the heck to find them or how to determine what was the last drive I used for the backups within Time Machine.  Help please.

  • HT4848 Is it possible to partition an external hard drive that is already being used for Time Machine backups without it being erased?

    I'm want to use my current external hard drive, which I use for Time Machine Backup, as a recovery disk for Mac OS X Mountain Lion 10.8.2. From what I have read, the recovery disk assistant will erase all data on the external drive unless it is partitioned. Can I partition my current backup drive without erasing it, even though it is already being used for Time Machine?

    It's very simple to test.  Turn off your computer.  Have your time machine backup plugged in.  Hold option and turn it on, keeping option held.  Do you see your time machine drive?  If so, select it and press enter. You'll end up in recovery.  If it works, there you go.  Then just click the apple and restart to get back to your regular desktop.  Then you'll know for when you're ready to do the deed.
    Edit...
    I'm not sure if time machine will think it's an entirely different computer, though, when a hard drive changed, making an actual restore not doable.  Either way, you could still reinstall mt lion fresh and then just migrate after, skipping the need for SL.

  • Is it possible to use an external hard drive for time machine backup and also as a regular hard drive?

    Is it possible to use an external hard drive for time machine backup and also as a regular hard drive?

    I am using an external drive in the exact way that you described. You just keep it plugged in to the computer when you want to access the movies and files. In order to put files on it, just go to finder open up the drive under devices and drag and drop files onto the drive. It is just like using a usb drive with a terabyte of space.

  • Mac OS X will not install as it states Mac HD is used for Time Machine backups?

    I'm not sure what is happening?! I wanted to connect my new wireless trackpad but could not as my mac said I needed 10.6 or later. I checked my mac which I thought had snow leopard on but it states it has 10.5.8? I am now trying to re-load mac OS X from my disc as it states it is 10.6 but it will not load as the installer gets to a point where it states that the Macintosh HD is used for Time Machine backups and consequently will not move on to the next stag? Now I cannot even get out of installing or eject the disc! Can anyone help with what I am doing wrong? VMT

    The installer won't load on any HD that contains a Backups.backupdb (used for Time Machine/Backup) folder on it.  If the backup isn't in use, delete that folder and 10.6 will install.
    Regards,
    Captfred

  • In the installation process lion will not install as message  reads MAC HD 904 gb available this disk is used for time machine backups .What is the next step

    After downloading ,completing the lic agreement phase, the next step is where to install and automatically' MAC HD with 904 gb available this disk is used for time machine backups' is shown and installation is blocked .
    Any body got any idea what to do next ?

    Time machine needs its own partition to operate. So you are not going install a OSx Lion on that volume.
    If there is enough room you may be able to partition the drive on the fly with DiskUtility
    Are you saying you clean installed Lion and you are trying to move your user Data over with TM via the migration Assistant?  Please explain.

Maybe you are looking for

  • How to use Transaction in Stateless SessionBean?

    I want to use a transaction in a stateless sessionbean.Here is the code I am using: public void createQuestion(QuestionModel questionModel,Collection outcomeList) throws Exception{ UserTransaction ut=getUserTransaction(); try{ QuestionHome qHome=EJBU

  • Javax.servlet.* Not Found Error - Please help

    I am having a great deal deal of trouble trying to compile a program using javax.servlet and javax.servlet.hhtp.*. I have setup the JAVA_HOME and the CLASSPATH variables as per the Installation instructions. I appear to have hit a brick wall and I am

  • HOW TO USE a sequence in merge load

    Hi, Someone can help me with a solution for loading a table with merge option and one of the column has values from a sequence. regards Babu

  • Dual Layer DVD - Formatting Failed

    I've bene trying to format a dual layerDVD project for the past few hours and I keep getting a Formatting Failed" message and Layer 1 cannot exceed Layer 0 for a OTP disc. I've tried shifting the layer break point all over the place to no avail - is

  • HP scanned pdf's are incompatible to other users

    I purchased this printer last week.  I used the scanner for the first time yesterday, and all the docs scanned and saved as PDF on my computer.  I am able to open them, but when I emailed them to other coworkers, they could not open those scanned pdf