HP StorageWorks XP Remote Web Console Software - Manual (Page 27)

External Storage XP user guide 27
Figure 8 Alternate path mode is Single mode with alternate paths in Standby only
NOTE: External arrays with Active/Standby (A/S) controllers, such as the MSA, are an example
of Figure 8 . A notable characteristic of using A/S controller arrays as external storage is that there
is typically only a single port to the owning controller. Paths to the non-owning external controller’s
ports are shown as Standby status. I/O load balancing does not occur across external controllers.
Powering arrays on or off
This section describes procedures for powering local and external arrays on or off after External Storage
XP operations have started.
These procedures use the following commands:
• Disconnect Subsystem
Execute the Disconnect Subsystem command from the Command View XP or XP Remote Web Console
GUI when you need to perform maintenance or stop the local or external array. This command stops
acceptance of all host I/O operations to the external LU mapped as the internal LDEV. All outstanding
data in cache memory on the local array intended for the external LU is written (de-staged) to the
external LU.
For instructions on executing the Disconnect Subsystem command, see ”
Disconnecting external arrays
or LUs ” on page 98.
NOTE: To disconnect an individual LU, use the Disconnect Volume command. To delete a single
external LU’s mapping, use the Disconnect Volume command and then the Delete LU command. For
instructions, see ” Deleting external LU mappings (Delete LU) ” on page 104.
• Check Paths & Restore Vol.