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maybe i'm too stupid, but what's the command to format my external 2.5tb usb hdd to ext3? using mkfs.ext3 /dev/sdc1 works, but only gives me 300gb of space allocated... where am i failing?

thanks in advance.

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migrated from serverfault.com Jan 23 '12 at 19:33

This question came from our site for system and network administrators.

up vote 3 down vote accepted

Run parted:

parted /dev/sdc

and do the following in it:

mklabel gpt
mkpart primary ext3 4MiB -1MiB

Only then try to format it:

mkfs.ext3 /dev/sdc1

As a side note: fsck on a 2.5TB partition will take a long long time, use ext4 if you can, jfs or xfs otherwise.

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+1 for using ext4. mkfs also takes forever on a disk that big with ext3. With ext4 it should only take a few seconds. – psusi Jan 23 '12 at 19:40

Are you using a master boot record partition table? If so, that could be the problem. MBR partition tables are only good up to 2 TB. Use GPT instead (GUID Partition Table, http://en.wikipedia.org/wiki/GUID_Partition_Table).

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when using GPT i can't mount it, really don't know why... i try to reformat! thanks – Tronic Jan 23 '12 at 14:52
@Tronic: can you give last few lines of output from dmesg when you try to mount the partition on GPT partitioned drive? – Hubert Kario Jan 23 '12 at 16:46

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