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I'd like to know how I can specify the cluster size when using mkdosfs /dev/sdx -F 32. I read somewhere that if you want to format it with a 32kb cluster size, this is the command:

mkdosfs /dev/sdx -s 64 -F 32 -I

But, what if I want to format it with a 64kb cluster size? How can I do it? Can someone explain the proper usage of mkdosfs /dev/sdx -s XX in plain words (I'm not a native english speaker)?

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1 Answer 1

up vote 2 down vote accepted

I believe the command is:

sudo mkdosfs /dev/sdXX -s 128 -F 32 

Since you want 64KB clusters, and the -s means sectors per cluster so, you need 128 sectors, because 128*512 byes = 64KB, making a cluster.

If you want the whole disk to contain a single partition, you would use -I option. So, the command becomes,

sudo mkdosfs /dev/sdX -s 128 -F 32 -I

Credit goes to this Ubuntu forum thread

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thanks, this was exactly the info i was looking for, i mean the sectors*bytes thing... –  Hairo Sep 18 '12 at 13:40
Note that Windows older versions don't support 64K or larger cluster sizes so if you need cross compatibility you might not want to do this: See –  Elder Geek Apr 6 at 17:13

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