Accéder à une partition GPT

1. Check the kernel was compiled with EFI support. The standard kernel with Debian Lenny comes with EFI support built-in. The command to check is:
cat /boot/config-2.6.26-2-686 | grep EFI
You know if the kernel was compiled with EFI support if you get these lines:
CONFIG_EFI=y
CONFIG_FB_EFI=y
CONFIG_EFI_VARS=m
CONFIG_EFI_PARTITION=y

2. The fdisk command shows only a placeholder partition. This is normal.
fdisk -l /dev/sda
WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! 
The util fdisk doesn't support GPT. Use GNU Parted.
Disk /dev/sda: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x00000000

  Device Boot      Start         End      Blocks   Id  System
  /dev/sda1               1      121602   976762583+  ee  EFI GPT

3. List the real partitions on the disk using parted.

parted /dev/sda print
You should get a result like this:
Number  Start   End     Size    File system  Name     Flags
1      17.4kB  1024MB  1024MB  ext3         primary
2      1024MB  6144MB  5120MB  xfs          primary
3      6144MB  6144MB  512B                 primary
4      6144MB  6144MB  512B                 primary
5      6144MB  7168MB  1024MB  linux-swap   primary
6      7168MB  992GB   985GB   xfs          primary

To mount the second partition, use the mount command in the same way you usually would.

mount -t xfs /dev/sda2 /mnt/test