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What is the hard disk drive partition naming convention in Linux (for example : [hd0,0] etc...)? What does it actually mean?

What is the significance of this when I need to install multiple operating systems on the same machine?

How can we relate it to Windows partitioning (example: C:\ drive or D:\ drive) ?

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There are actually two conventions for naming hard-disk devices and partions: one is the Linux "traditional" way (explained in user4124's reply), the other is the GRUB way (explained in pheedrus answer). Unfortunately, one must be aware of both. – Riccardo Murri Oct 15 '10 at 18:16
Cross-posted to… – Riccardo Murri Oct 15 '10 at 18:19

I think now most hard disks use the SCSI interface, therefore the device is not /dev/hdx but rather /dev/sdx. USB sticks and external USB hard disks use the SCSI interface (therefore /dev/sdx). The same goes with eSata external hard disks.

As the devices are connected to the system, they occupy the next available drive letter.

For the first hard disk, /dev/sda is the raw hard disk (it points to the start of the raw hard disk). The partitions are /dev/sdaN, where N=1,2,3,4,5,6... With the DOS compatible partitioning, you get four primary partitions (1 to 4). One of those primary partitions can be an extended partition, which means that you can further partition the interior to more partitions. In this case, the first of those, called logical partitions, is /dev/sda5. Further logical partitions are 5, 6, 7, ... Typically you create a big extended partition and then you can add as many logical parititons as you wish.

For the mapping of Windows partitions (for example, which is C:), you need to find a Microsoft report which explains how the operating system assigns driver letters. There is a report on their website, I do not have the URL handy :-(.

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Thanks you very much – Renjith G Oct 15 '10 at 21:05

The first element in this case hd0 represents a physical hard drive in your system. The 0 represents the first one it has detected. For example if you have two IDE hard drives, the first one would be hd0 and the other one would be hd1 and so on. The second element namely the ,0 represents a given partition within that hard drive. So in the case of hd0,0 this would represent the first partition on the first hard drive. So if you had a boot partition in this reference with grub loaded on it you would define hd0,0 as your boot partition in your Grub conf file.

Hope this helps.

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Thanks you very much – Renjith G Oct 15 '10 at 20:41

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