If I have a 500GB drive on my iMac do I need a to have a 500GB external drive or can I use a smaller amount, say 350GB? What will the effects be?
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Time Machine Hard recommended Hard drive Size?
- Thread starter Mikebike125
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Well, that depends on a number of factors, chiefly how much space you use on the drive and how often you change large files. Since Time Machine does incremental backups, it will only save files that have been updated in subsequent backups.
Personally, I size my Time Machine partition to provide half again as much space as is used on my main drive. I have a 320 GB drive, but only about 80 GB of data, so my Time Machine partition is roughly 120 GB (I don't have the drive connected so I can't say for certain how much space I'm using).
Personally, I size my Time Machine partition to provide half again as much space as is used on my main drive. I have a 320 GB drive, but only about 80 GB of data, so my Time Machine partition is roughly 120 GB (I don't have the drive connected so I can't say for certain how much space I'm using).
Whaat, you were right! I don't really have anything else to add.
B-b-but i like to learn how things work
You dont have any other facts or anything?
It depends more on used space then anything else. I've used Time Machine with smaller hard drive since what I want to have backed up is still much less then the total disk capacity.
right no i have a 500 gig internal and a 250 gig external for time machine
as you can see there may be an issue lol so what you have to do is decide what things to exclude
Possibly it compresses the data? Not sure. I am currently using exactly 138GB not including my movies. I don't mind not backing up the movies because they can be re obtained if lost. I wonder if TM is smart in that it doesn't back up the OS because that is obviously on a DVD.....
I can't seem to find any info or advice on the Apple website. Surely they have some recommendation........
No, it doesn't.
Then I'd say a 250 GB backup drive would be plenty.
... which would mean you'd need even less space.
Here is some data from my Time machine Discoveries.
I have a 500GB iMac there is 363.01GB available which means that 136.99GB have been used.
I got a 1TB external HD and partitioned it into two drives each having 465.76GB
After Time Machines first back up there was 383.11GB left which means that Time Machine only backed up 82.65GB of stuff. I put no limitations on what TM backed up so essentially I asked it to back up everything.
This leads me to believe that TM probably does not back up the OS which makes sense. Anyone else have any explanation about the missing GB's???
I have a 500GB iMac there is 363.01GB available which means that 136.99GB have been used.
I got a 1TB external HD and partitioned it into two drives each having 465.76GB
After Time Machines first back up there was 383.11GB left which means that Time Machine only backed up 82.65GB of stuff. I put no limitations on what TM backed up so essentially I asked it to back up everything.
This leads me to believe that TM probably does not back up the OS which makes sense. Anyone else have any explanation about the missing GB's???