Hi Luca, On 04/21/11 02:15, Luca Berra wrote:
If someone here still believes that drives from different vendors with the same nominal size have different real size please read: http://www.idema.org/wp-content/plugins/download-monitor/download.php?id=1192
I don't think my point is invalid. If you wanted to mix SSDs and spindle HDDs (for, say, write-mostly "backup" of the SSDs), quite likely your drives will be of different sizes, as the SSDs frequently come in sizes that are power of two's unlike the spindle drives. You could start of with just one type of drive, and only then come up with the idea of mixing types, etc. Probably not the best example, but one nonetheless.
There are other benefits to using a partition instead of the whole device. For example, you could use a GPT label, which allows you to label individual partitions. In an earlier post, I sent out a gpt_id script and UDEV rules which insert /dev/disk/by-label/ links for you to GPT-labeled partitions. We use it at the CS department of U of Toronto to keep track of the physical location of disks (within iscsi target hosts).
I think that if you are not interested in the 2nd point here, you could simply use the --size option to mdadm to use less than the total capacity of the drives, but apparently it doesn't work for all RAID levels (RAID 10 is not listed in Debian Lenny's man-page). Somebody correct me if I am wrong about this.
Cheers! Iordan -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
