Network Administration: Disk Partition Planning
Partitioning enables you to divide a physical disk into one or more separate units called partitions. Each disk can have up to four partitions. All four of the partitions can be primary partitions, each of which can be formatted with a different file system, such as NTFS or FAT32.
Or you can create up to three primary partitions and one extended partition, which can then be subdivided into one or more logical drives. Then, each logical drive can be formatted with a file system.
Although you can set up partitions for a Windows server in many ways, the following two approaches are the most common:
Allocate the entire disk as a single partition that will be formatted with NTFS. The operating system is installed into this partition, and disk space that isn’t needed by the operating system or other network applications can be shared.
Divide the disk into two partitions. Install the operating system and any other related software (such as Exchange Server or a backup utility) on the first partition. If the first partition will contain just the operating system, 10GB is a reasonable size, although you can get by with as little as 4GB if space is at a premium. Then, use the second partition for application data or network file shares.
Note that the disk partitioning scheme is independent of any hardware-based RAID configuration your server might employ. For example, your server might actually include five physical hard drives that are combined by the hardware disk controller to form a single logical drive. Within this logical drive, you can create one or more operating system partitions.