The physical disk is a logical unit (LUN) that is assigned by storage unit. LUN is a storage medium that actually stores data and is one of the components of a virtual disk.
The physical disk must be registered in an arbitrary virtual storage pool.
Before registering a physical disk with the virtual storage pool, check whether any transaction server is using the physical disk for any other purpose. Once a physical disk is registered, it remains available only as a virtual disk.
If a physical disk is accessible from multiple channel adapters (CA), WWPNs assigned to all accessible CAs along with a logical unit number (host LUN) are required for registering it.
Figure 2.3 Registration information of the physical disk
For the storage shown above, two CAs can access each physical disk. Thus, when you register one physical disk, you will need two items of CA (WWPN) information and the corresponding host LUN information.
You can release any physical disk that will no longer be used from the virtual storage pool. However, if a physical disk is a component of a virtual disk, you cannot release that physical disk from the virtual storage pool. A physical disk released from the virtual storage pool can be connected to the transaction server and can be used as before.
