Limits - Overview

Limits of the Containers

The containers are the transparent layer between the user and the filesystem. Here are some limits:

There is also a blanket limit for each container type. There can only be 32:

• Partitions in a striped volume
• Partitions in a RAID5 volume
• Partitions in a spanned volume
• Mirrors of a simple, or striped, volume

Limitations of Windows

Microsoft don't support Dynamic Disks on laptops, removable disks, USB or FireWire interfaces.

You cannot mix Basic and Dynamic Volumes on on disk. Once a disk is upgraded to a Dynamic Disk, it cannot be reverted to a Basic Disk, without first removing all the Dynamic Volumes it contains.

N.B. If you upgrade to a Dynamic Disk, then any partitions, except NTFS and FAT, will show up as free space after the conversion.

Although LDM doesn't need a DOS-style partition, there'll still be one. This is partly to prevent legacy applications thinking that there is free space on the disk, when there isn't. Importantly, though, it's needed to boot Windows. The boot code relies on the operating system being in a primary partition.

Because booting is reliant on simple, BIOS, calls, you cannot extend the boot volume in any way.

If you create a dynamic disk, then create partitions, you will not be able to install windows on it because it requires a primary partition.

Windows can only dynamically resize NTFS volumes.

Veritas' LDM is a very powerful, robust partitioning scheme. Most of the limitations, above, are because Microsoft hasn't updated all the disk infrastructure to match.

Microsoft have only added LDM to Windows 2000 and XP. Any other versions of windows cannot read from dynamic disks.