RAID offers the option of combining numerous disks together so that they look like one logical disk. This can help in providing ways of providing redundancy, or speed by spreading the data across different disk platters. Linux supports both hardware and software RAID. Hardware RAID is handled by the disk controller, without any help needed from the kernel.

Software RAID is controlled by the kernel, and can be selected as a build option:

Device Drivers
    Multi-device support (RAID and LVM)
        [*] Multiple devices driver support (RAID and LVM)
        [*]   RAID support

There are many different types of RAID configurations. At least one needs to be selected in order for RAID to work properly:

Device Drivers
    Multi-device support (RAID and LVM)
        [*] Multiple devices driver support (RAID and LVM)
        [*]   RAID support
        [*]     Linear (append) mode
        [*]     RAID-0 (striping) mode
        [*]     RAID-1 (mirroring) mode
        [*]     RAID-10 (mirrored striping) mode (EXPERIMENTAL)
        [*]     RAID-4/RAID-5 mode
        [*]     RAID-6 mode

Much like RAID, LVM (Logical Volume Manager) allows the user to combine different block devices to look like one logical device. However it does not work on a device level like RAID, but through a block and sector mapping mechanism. It allows different portions of different disks to be combined together to look like one large block device to the user. To do this, the kernel uses something called Device Mapper (DM).

To enable Device Mapper support in the kernel:

Device Drivers
    Multi-device support (RAID and LVM)
        [*] Multiple devices driver support (RAID and LVM)
        [*]   Device mapper support

There are a number of helper modules that work with Device Mapper to provide additional functionality. You should enable them if you wish to encrypt your devices, or allow snapshot functionality:

Device Drivers
    Multi-device support (RAID and LVM)
        [*] Multiple devices driver support (RAID and LVM)
        [*]   Device mapper support
        [*]     Crypt target support
        [*]     Snapshot target (EXPERIMENTAL)
        [*]     Mirror target (EXPERIMENTAL)
        [*]     Zero target (EXPERIMENTAL)
        [*]     Multipath target (EXPERIMENTAL)

Samba is a program that allows Linux users to access Windows machines natively across the network, providing a way to share drives and devices in a transparent manner. It also allows Linux to work as a Windows server, allowing Windows clients to connect to it thinking that it is a real Windows machine.

Two different filesystems that allow a Linux machine to connect with a Windows machine: the SMB filesystem and the CIFS filesystem. For the ability to connect to older Windows for Workgroups or Windows 95 or 98 machines, select the SMB filesystem:

File systems
    Network File Systems
        [*] SMB file system support (to mount Windows shares etc.)

For the ability to connect to newer Windows machines, the CIFS filesystem is recommended instead:

File systems
    Network File Systems
        [*] CIFS support

For more details on the differences between these two filesystems, and when one should be used instead of the other, please see SMB_FS and CIFS.

OCFS2 is a cluster filesystem from Oracle that works for large network installations and small local systems at the same time. This filesystem is recommended when using large databases, such as Oracle or DB2, because it can be moved over time to different backing disks across the network quite easily as more storage is needed.

To enable the filesystem:

File systems
    [*] OCFS2 file system support