Disk units store data. The server can use and reuse this data at any time. It is more permanent than memory, but you can still erase it.
You cannot separate the disk units on an IOP into different logical partitions. You can create user auxiliary storage pools (ASPs) on any logical partition. However, you cannot create a cross-partition ASP. All of the disk units you assign to an ASP must be from the same logical partition.
You can also create an independent auxiliary storage pool (ASP). An independent ASP is a collection of disk units that can be taken offline, or made unavailable, independent of other disk pools because the data in the independent ASP is self-contained. The independent ASP can also be brought online, or made available, while the system is active, without having to perform a restart.
The server maintains the logical partition configuration data on the disk unit that you designate as the load source for each logical partition.
When you move disk units, you may need to clear any logical partition configuration data that is contained on them.