IMPORTANT: Les noves versions d'Ubuntu (TODO: A partir de quan?) utilitzant el sistema de particions GPT. Tingueu en compte a l'hora de recuperar dades d'aquests discos ja que utilitzant eines tradicionals com fdisk les particions no es detectaran i us pot semblar que teniu un disc buit sense particions!
In computer hardware, GUID Partition Table (GPT) is a standard for the layout of the partition table on a physical hard disk. It forms a part of the Extensible Firmware Interface (EFI) standard, which is Intel's proposed replacement for the PC BIOS. It is also used on some BIOS systems because of the limitations of MBR partition tables. GPT allows for a maximum disk and partition size of 9.4 zettabytes (9.4 × 1021 bytes). As of 2010, most current operating systems support GPT, although some operating systems (including Mac OS X and Windows) require systems with EFI hardware to support booting from GPT partitions.
The MBR partition table restricts partition sizes to a maximum of 2.19 terabytes (2.19 × 1012 bytes) or almost exactly 2 TiB (2,199,023,255,552 bytes or 4,294,967,296 (232−1) sectors × 512 (29) bytes per sector). GPT supports partition sizes up to 9.4 zettabytes or 8 ZiB−512 bytes (9,444,732,965,739,290,426,880 bytes or 18,446,744,073,709,551,615 (264−1) sectors × 512 (29) bytes per sector). Diagram illustrating the layout of the GUID Partition Table scheme. In this example, each logical block (LBA) is 512 bytes in size, and each partition entry is 128 bytes. LBA addresses that are negative indicate position from the end of the volume, with −1 as the last addressable block.
The widespread MBR partitioning scheme, dating from the early 1980s, imposed limitations which affected the use of modern hardware. Intel therefore developed a new partition-table format in the late 1990s as part of what eventually became UEFI. The GPT as of 2010 forms a subset of the UEFI specification.
Que mostra fdisk:
$ sudo fdisk -l ... Disk /dev/sdb: 500.1 GB, 500107862016 bytes 255 heads, 63 sectors/track, 60801 cylinders, total 976773168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0xcdf8556a Dispositiu Arrenc. Inici Final Blocs Id Sistema /dev/sdb1 * 63 976768064 488384001 83 Linux WARNING: GPT (GUID Partition Table) detected on '/dev/sdc'! The util fdisk doesn't support GPT. Use GNU Parted.
Com podeu veure cal utilitzar l'eina parted.
$ sudo parted -l Model: ATA OCZ-AGILITY3 (scsi) Disk /dev/sda: 120GB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 1049kB 103GB 103GB primary ext4 boot 2 103GB 120GB 17,1GB extended 5 103GB 120GB 17,1GB logical linux-swap(v1) Model: ATA ST3500820AS (scsi) Disk /dev/sdb: 500GB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 32,3kB 500GB 500GB primary ext3 boot Model: ATA Hitachi HDS72101 (scsi) Disk /dev/sdc: 1000GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags 1 17,4kB 20,0MB 20,0MB fat16 bios_grub 2 20,0MB 996GB 996GB ext4 3 996GB 1000GB 4178MB linux-swap(v1)
Suposem que és el tercer disc (/dev/sdc):
$ sudo parted /dev/sdc (parted) set Warning: /dev/sda contains GPT signatures, indicating that it has a GPT table. However, it does not have a valid fake msdos partition table, as it should. Perhaps it was corrupted -- possibly by a program that doesn't understand GPT partition tables. Or perhaps you deleted the GPT table, and are now using an msdos partition table. Is this a GPT partition table? Yes/No? yes Partition number? 1 Flag to Invert? bios_grub New state? on/[off]? on
I ja teniu la partició recuperada.