External storage systems

An external storage system, or storage controller, is a device that coordinates and controls the operation of one or more disk drives. A storage system synchronizes the operation of the drives with the operation of the system as a whole.

If you have configured logical unit names (LUNs) on your external storage systems, it is not possible for the system to determine this name, because the namespace is local to the external storage system. However you can use the external storage system WWNNs and LUN IDs to identify each device. This unique ID can be used to associate MDisks on the system to the corresponding LUNs on the external storage system.

Select Pools > External Storage in the management GUI to view all MDisks detected by the system. The MDisks are organized by the external storage system that presents them. To display the unique ID that is associated with the external storage system, use the filter function in the management GUI to display the UID column. If new external storage is added to the system, select Actions > Discover storage. If no MDisks display, ensure that you have cabled the system correctly to the external storage system.

Note: You can also issue the lsmdisk command to display information about the MDisks that are visible to the system. The command output contains detailed information about the node canister with the lowest node ID number. However, both node canisters have access to the MDisks.

In general, pools that consist of single-port attached systems are not supported. However, HP StorageWorks MA and EMA systems that contain array partitions can only be attached to the system through a single-port attach mode.