Can't create filesystems larger than 2TB

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Environment

SUSE Linux Enterprise Server 11
SUSE Linux Enterprise Server 10
SUSE Linux Enterprise Desktop 11
SUSE Linux Enterprise Desktop 10

Situation

When trying to create a file system larger than 2TB, a (much) smaller file system is created instead.

Resolution

The "GPT" disk labeling scheme needs to be used in order to be able to create partitions larger than 2 TB. When you use the default "msdos" disk labeling scheme, you are limited to four partitions of just under 2 TB. If you want to use the disks, regardless of the disk labeling scheme as data drives, you have the following options:
1. Format the entire drive with a file system, without partitioning the drive.
2. Create partitions smaller that 2 TB, and add them to an Logical Volume Manager (LVM) volume group, then create a logical LVM volume greater than 2 TB. Once the logical volume is created, you can format it with a file system of your choice.
3. You can use the Enterprise Volume Management System (EVMS) volume manager in a similar way as described in step 2 above.

Additional Information

Change the Disk Labeling Schema

The parted tool can be used to change the partition labeling scheme of a disk.

WARNING: The following procedure will erase all data and partitioning on the block device!

Open the block device for the disk in parted:
parted /dev/sda
Create the GPT partition label:
mklabel
Set the label to GPT:
gpt
Leave parted:
quit
Check that the label of the partition is now set to "EFI GPT" by using
fdisk -l /dev/sda

or

parted /dev/sda

and press "p".

The existing partition table will be destroyed and the disk can now be repartitioned using the GPT disk labeling scheme

Root Cause

This problem is caused by the limitations of the disk label (partitioning scheme).

For disks partitioned using fdisk or partitioned as part of a default yast2 installation, the disk label will be ms-dos (the traditional PC disk labeling scheme). With this disk label, the maximum size of a partition is limited to 2 TB.

GPT - GUID Partition Table - is a more recent partitioning scheme which does not have the 2 TB limit for individual partitions.

parted note

As of this writing, parted version 1.7.1 can only create ext2, FAT32, FAT16, and linux-swap filesystems. For other filesystem (reiserfs, ext3, OCFS2 etc.), the appropriate mkfs tool needs to be used, e.g.

mkfs -t <TYPE> /dev/the_partition

mkfs.<TYPE> /dev/the_partition

Status (Last updated: 2009-06-23)

YaST2 in SLE11 has an option to change the disk label and to boot from GPT disks. A feature request for SLE10 SP3 functionality has been logged with Engineering.

Additional Reading

The wikipedia article GUID Partition Table provides background on GPT.

Disclaimer

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