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Partitioning my Hard Drive

j3tang said:
I think virus1 was just being sarcastic about using the PC .. probably what he meant was why format to FAT so that you can use it on the PC if you shouldn't be using the PC in the first place :p
Click to expand...

Actually no.. the steps outlined in the linked hint requires the use of a PC.
 
mrichmon said:
Yes. It is easiest to do using OS X 10.4.6 since there are some additional options available in Disk Utility. Connect the disk to the Mac and open Disk Utility. Use the partition tab to create a "Master Boot Record" partition table on the disk (the partition type is found under the "Options" button).

Partition the drive and specify the formats that you want the partitions to have.

With earlier versions of OS X, you need to first connect the drive to a Windows machine and use Disk Management to create the FAT32 partition(s) you want on the drive. Then connect the drive to a Mac and use Disk Utility to create your HFS+ partition in the remaining free space on the disk.
Click to expand...
Yes, except for whatever reason -- and whatever partition table format I tried -- Disk Utility on my OS X 10.4.7 machine could not create any HFS+ partitions on my 250GB external USB drive, let alone HFS+ and FAT. Believe me, I tried. Several times and several different ways. With and without a FAT partition. With and without a Windows involved.

What I finally did -- and this is not complete success -- was installed TransMac on a PC and used it to format the whole disk as HFS+. (It could not format just a partition; only the whole drive.)
 
straightup said:
Yes, except for whatever reason -- and whatever partition table format I tried -- Disk Utility on my OS X 10.4.7 machine could not create any HFS+ partitions on my 250GB external USB drive, let alone HFS+ and FAT. Believe me, I tried. Several times and several different ways. With and without a FAT partition. With and without a Windows involved.
Click to expand...

Ahh, a USB drive. Yes, I've encountered problems with using Disk Utility with a USB drive myself. I got around the problem one time by using "dd" to write zeros to the beginning of the disk... say the first 10MB. With other USB drives I just ended up downloading the GParted LiveCD and using GParted to partition the drive then used Windows and OS X to format the partitions as appropriate.
 
WinXP has a built-in limit for formatting FAT32 partitions (32gb I think). I want a common format mountable by my NAS, Mac and PC - which means FAT32. And I want at least a 200Gb partition. How do I do this? Thanks
 
Your Mac can format FAT32 and has no self-imposed limitation (Microsoft imposed it to encourage the move to NTFS).
In Disk Utility it's "MS-DOS".
 
Oh yeah - could someone explain the minimum block sizes of FAT32? OK to format a 400Gb as one partition as long as I'll mainly be storing MP3's and Apple Lossless files on it?
 
About optimising the size of the drive based on the number of block it was being formatted with and therefore the increasing size of each block being a waste of space when storing smaller files? Something like that? I'm aware of the 4Gb limit
 
Ok this is how i think you do it (I did it a year ago so its from memory)

you go into terminal and type

disk util list
you will get something like this


#: type name size identifier
0: Apple_partition_scheme *55.9 GB disk0
1: Apple_partition_map 31.5 KB disk0s1
2: Apple_HFS Macintosh HD 55.8 GB disk0s3
/dev/disk1
#: type name size identifier
0: Apple_partition_scheme *462.2 MB disk1
1: Apple_HFS iDisk 462.2 MB disk1s2


then you plug in your hard drive that you want to partion

and see what changes

There will be a new disk

and therefore the one you want to partiton
then find the name of this disk, it will be something like

disk3



then type in the command below adjusting it for yourself
disk3 is the disk you want to partiton IT MAY NOT BE DISK3 FOR YOU

3 is number of partions

then it goes format e.g. HFS+ then name of partition e.g. mac then size e.g. 30g and repeat for each partion

FAT 32 is MS-DOS



the command is :

diskutil partitionDisk disk3 3 MBRFormat HFS+ Mac 100G HFS+ Mac2 30G MS-DOS PC 10G
 
Matt Phoenix said:
Okay, I know there have been threads made about partitioning a hard drive, but I couldn't find one that deals with my specific problem. I have a 250GB hard drive, which I originally planned to divide up into 3 partitions (one I could boot from if I need to, one for large media projects and important files, and one in the FAT32 format so I could transfer files from PC to Mac and vice versa). Using Disk Utility, I was able to make three partitions, all of which were FAT32, or all of which were HFS+ (which is what they are currently), but I am unable to find out how to make individual partitions different and not have them all be the same (like keep 2 as HFS+, but make the third one FAT32). How would I go about doing this?
Click to expand...


Yes but deals with the original partition problem, no pc needed
 
Sesshi said:
Oh yeah - could someone explain the minimum block sizes of FAT32? OK to format a 400Gb as one partition as long as I'll mainly be storing MP3's and Apple Lossless files on it?
Click to expand...

You'll be fine with the default block size. In general you don't want to mess with block sizes for any filesystem unless you are going to be storing a massive number of very small files or require very specific performance from the filesystem such as when running a transaction processing system.

Of all the file systems out there, FAT is the one file system that it is very much not worth messing with block allocation sizes. You really don't get much real world benefit from messing with FAT block sizes and for general file storage such as documents, mp3s and videos it is not worth it.
 
mrichmon said:
You'll be fine with the default block size. In general you don't want to mess with block sizes for any filesystem unless you are going to be storing a massive number of very small files or require very specific performance from the filesystem such as when running a transaction processing system.

Of all the file systems out there, FAT is the one file system that it is very much not worth messing with block alllocation sizes. You really don't get much real world benefit from messing with FAT block sizes and for general file storage such as documents, mp3s and videos it is not worth it.
Click to expand...


Okey dokey.

Another question. So the Disk Utility partitons and writes the MBR and FAT for FAT32 partitions when you set via options to write an MBR then select to create a MS-DOS partition. Given the time it takes to prepare, it's obviously not actually going through all the sectors. Is there a way to 'actually format' (i.e. scan all sectors) a FAT32 partition on a Mac? I'm doing it on a PC now but next time I do it I'd like to know.
 
yellow said:
Seriously, I thought all blocks were 512bytes, and this was not a user-editable thing.
Click to expand...

For many filesystems (ext2, HFS+, UFS, etc) the block size can be specified when the disk is formatted. If the size is not specified it defaults to a size that is usually calculated based on the size of the partition together with some estimates of typical file sizes. On modern disks the block size is usually one of 0.5KB, 1KB, 2KB, or 4KB.

A small number of filesystems, specifically ZFS allows for variable block sizes.

For general disk use there is no need to mess with using block sizes that are different from the default for the filesystem you are using.
 
Sesshi said:
Is there a way to 'actually format' (i.e. scan all sectors) a FAT32 partition on a Mac? I'm doing it on a PC now but next time I do it I'd like to know.
Click to expand...

In Disk Utility the closest is named "Erase Free Space". That is, erase the unallocated space in the selected filesystem. In general, if you are concerned about wanting to do a full sector scan then you are better off doing it on a PC.
 
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