4.1.0 HP PolyServe Matrix Server administration guide (T5392-96073, October 2010)

subdevice, and then to the third subdevice. This method fills the subdevices at the
same rate and may provide better performance.
• Concatenation. When a dynamic volume is created without striping, data is
written to the first subdevice until it is full. Then data is written to the second sub-
device, and so on.
Dynamic volume names
The Cluster Volume Manager uses unique device names to control access to dynamic
volumes. These names form the pathnames that servers use to access shared data.
When you create a dynamic volume, the Volume Manager gives it a global device
name. The name consists of psv followed by an integer. For example, psv1, psv2,
and psv25 are all valid names.
Matrix Server stores information about dynamic volumes in a volume database located
on the membership partitions.
Volume signature
When a dynamic volume is created, a volume signature is written on each subdevice
in the volume. The signature specifies the volume to which the subdevice belongs.
When a dynamic volume is deported, the subdevices making up the volume will
retain their volume signatures, allowing the volume to be reassembled when it is
imported again.
Configuration limits
The configuration limits for dynamic volumes are as follows:
• A maximum size of 32 TB for a dynamic volume on 64-bit operating systems.
• A maximum of 128 dynamic volumes per cluster.
• A maximum of 128 subdevices per dynamic volume.
• Concatenated dynamic volumes can be extended up to 128 times; however, the
total number of subdevices cannot exceed 128.
• Striped dynamic volumes can be extended up to 16 times; however, the total
number of subdevices cannot exceed 128.
Guidelines for creating dynamic volumes
When creating striped dynamic volumes, follow these guidelines:
Configure dynamic volumes84