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Использование parted для разметки диска

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Instead of using a whole device for linux software RAID, use a partitioned device which mean the device has an easily read 'label'. This means I can determine that it is a RAID member disk (as a against a standalone disk) just by looking at the partition table. However it can introduce alignment issues, which are mitigated by starting the partion at offset 1MB.

==== Steps ====

Run parted as root to create a partition table and raid partition.

<code>
# parted -a optimal /dev/sdf
</code>

Create a legacy master boot record (MBR) partition table

<code>
(parted) **mklabel msdos **
</code>

Create a partition that is optimally alligned starts at 1MB into the disk (2048 sectors) and ends at the end of the disk (-1).

<code>
(parted) **mkpart** Partition type?  primary/extended? **primary** File system type?  [ext2]?
Start? **2048s** End? **-1**
</code>

Mark the partition as a software raid partition

<code>
(parted) set 1 raid on
</code>

Verify the partition is aligned

<code>
(parted) align-check alignment type(min/opt)  [optimal]/minimal? optimal Partition number? 1
1 aligned
</code>

Show the device

<code>
(parted) **print** Model: ATA WDC WD3202ABYS-0 (scsi)
Disk /dev/sdf: 320GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number  Start   End    Size   Type     File system  Flags
 1   1049kB  320GB  320GB  primary               raid
</code>

Add the device to the Linux software RAID volume:

<code>
# mdadm --add /dev/md1 /dev/sdf1
</code>