Automatic Virtual Disk Expansion - NEC Express5800/320Ma Administrator's Manual

Using RDR for Fault Tolerance
"data about data" that the RDR software stores on disks to implement disk
management. When you configure a disk for RDR, the system displays an error
message if the disk does not have adequate space. The disk being upgraded should
be a basic disk.
Use RDR to mirror internal disks. To create large striped volumes, use your
disk-management tool to create striped volumes across the mirrored internal disks.

Automatic Virtual Disk Expansion

An RDR virtual disk includes an automatic disk-capacity expansion feature. If you
replace the physical disks (plexes) of an RDR virtual disk with larger physical disks,
RDR automatically recognizes the resulting larger virtual disk, which enables the
system to use the added disk capacity.
Note, however, that a virtual disk cannot be larger than the smaller of its two physical
disks.
For example, if each physical disk of an RDR virtual disk is 80 gigabytes (GB), the
virtual disk is an 80-GB virtual disk. If you replace one 80-GB physical disk with a
160-GB physical disk, the virtual disk remains an 80-GB disk, the smaller of the two
physical disks. But if you replace the other 80-GB physical disk with another 160-GB
physical disk, the RDR virtual disk automatically updates to 160 GB.
Disk Storage Management 4-3