Hard Drive to buy for Backup

Discussion in 'Buying Tips and Advice' started by soulred12, Jun 20, 2011.

  1. soulred12 macrumors member

    Jun 15, 2011
    I want to backup my MacBook Pro to an external HD. Problem is I'm on a college student's budget (i.e., not much) so I need to keep the cost to a (reasonable) minimum.

    My MBP's internal HD is 200GB, with 90GB currently used, and I want to create 2 partitions, one for a bootable duplicate and one for a Time Machine backup. Will a 500GB external Hard Drive be sufficient? I assume I need to partition it into 200GB/300GB...but I'm not sure that 300GB (or however much less based on the formatted capacity) is enough for a satisfactory backup. Searching these forums and google led me to a number of threads in which it was recommended that one should buy a backup drive that's 2x or at the very least 1.5x the size of one's internal HD...and 300GB just barely meets that (and, again, it misses the mark when considering actual formatted capacity).

    Is there another option for the bootable duplicate or is that even necessary/useful? Or would it be ultimately useless unless I go for e.g. 640GB or 750GB?

    And, I also read that TM is effectively locked into an hourly/daily/weekly schedule. Will the process still work well if I e.g. connect my MBP every sunday night and just backup weekly?

  2. gnasher729 macrumors P6


    Nov 25, 2005
    The backup drive for Time Machine should be at least twice the size of the data you use - in your case 2 x 90 GB, so 500 GB is plenty. You can probably save money by going for a 3.5" drive; 1 TB in 3.5" probably costs the same as 500 GB in 2.5" and would be more future proof. You can't carry it around as easily though and likely has its own power supply. That's what I use at home.

    I recommend adding one 10 GB partition and copying your installer DVDs on that partition (and check that you can boot from that partition), so in an emergency your backup drive contains everything you need to restore in one place.
  3. Brian33 macrumors 6502a

    Apr 30, 2008
    USA (Virginia)
    Don't forget that the 90 GB currently used will no doubt increase over time as you collect more stuff. However, that will probably take awhile, so if money is tight and if you really want a bootable clone, I think you're OK going with your plan of a 500 GB external drive. When your MBP's drive finally gets filled to near capacity, you'll be able to see how Time Machine is handling the 200 GB --> 300 GB partition. (I think it will handle it OK.) At that point, if you need to, you could get another drive for the bootable clone. (Or maybe even decide you don't need it (blasphemy!), but that's another subject...)

    Yes, Time Machine backups will work fine this way.

    However, I can't help but mention that the most desirable setup for a portable computer is wireless backup. Human beings have a tendency to either forget to plug in the external drive or get lazy about it, and then they won't have a good backup when they need it. With something like Time Capsule or a Time Machine supporting NAS, your MBP will back itself up whenever it's within range and turned on, eliminating the human error aspect. But, if costs are a big consideration, I think your approach is reasonable. Just remember to plug that external in, regularly!

  4. r0k macrumors 68040


    Mar 3, 2008
    I use timemachineeditor.app to tame time machine to once a day at 1am, otherwise that darn clock is spinning every time I sit at my machine. Also make sure you disable spotlight on any volume time machine is backing up to or you are in for long slow backups.

    I don't recommend backing up data to the same physical media. I know you are a college student but an external usb drive can be had for under $100 and maybe even under $50. Pass up a few pizza parties and get an external drive to back up to. You won't regret it as much as you might regret losing your machine along with your only copy of your data and backup either due to theft or accident. Never ever ever keep all your data in only one place, especially when money (or in your case grades) might be riding on the integrity of the data.
  5. soulred12 thread starter macrumors member

    Jun 15, 2011
    Thanks for the replies,

    @gnasher: Sounds reasonable, but I wonder, is is there any significant benefit that a full duplicate has over just copying over the installation files? Or are the installation files and the data backup all I really would need? (and could I copy my purchased snow leopard DVD over or would it have to be the original dvds that came with my MBP long long ago?)

    @Brian33: Thanks...Apple's Time Capsules are attractive (and they'd definitely be nice as a way to simplify this whole process of finding a backup drive) but I've read a lot about them failing and just generally being poor choices. Though, idk if all that was a reliable representation of the quality of the product or just a biased sample. Your idea of getting a second (smaller/cheaper) drive for a bootable clone though, is not a bad idea at all. Maybe in a few months when I have some extra cash again I can do that. Also: If I decide to go the bootable clone route, how often would you (or anyone) say I should update it?

    @r0k: Thanks for the advice, I will do both those things. And also, I was always planning to get an external HD, that's what this thread was about :)

Share This Page