local storage system. After the mapping, you can manipulate the external volume from the local storage system in the same way as manipulating an internal volume.
When external volumes in external storage systems are mapped as internal volumes in your storage systems, the external volumes can be accessed and copied by hosts connecting to your storage systems, but not by hosts connecting to the external storage systems.
This document sometimes uses the term external volume or mapped external volume to mention an internal volume where an external volume is mapped (see B in Figure 4 (page 14)), because this internal volume is a virtual representation of an external volume.
When you perform mapping, a path is automatically created between an internal volume and an external volume. This path is called a mapping path, which connects one volume with another volume. A
To use the external volumes that you mapped as an internal volume (see B in Figure 4 (page 14))
-from the host or other program products, the system administrator needs to create LDEVs in the external volume (see A in Figure 4 (page 14)). To create LDEVs, use XP External Storage at the time of mapping, or use the Virtual LVI/LUN (VLL) function on the internal volume where an external volume is mapped after mapping. The LDEVs created by these methods are called LDEVs in the external volume in this document. These LDEVs are usually called external volumes in other documents.
An external volume corresponds to a VLL VDEV (Virtual Device). An LDEV in the external volume corresponds to a VLL LDEV. Therefore, you can use the VLL function to create
XP External Storage Operations
Use XP External Storage to execute the following operations.
•Preparing to use external volumes
You can map external volumes, set port attributes, and set
•Preparing to manipulate the power supply of the storage systems
You must follow specific procedures to manipulate the power supply of the storage systems when external volumes are used. To turn on or off the power supply of the external storage system after starting to use the external volumes, you need to execute the commands of XP External Storage. For details, see “Turning On or Off the Storage System” (page 88).
•Setting up and removing the
When you set up or remove the path (cable) connecting the storage systems, you need to use XP External Storage to make settings on the path. For details on removal, see “Disconnecting External Storage System or Disconnecting External Volume” (page 91) and “Checking Connection Status and Resuming External Volume Operation” (page 93). For details on setup, see “Configuring the
•Referring to the status of external volumes
You can see the status and the configuration of external volumes. For details, see “Checking the External Volume Details” (page 85).
•Stopping the use of external volumes
You can cancel mapping of external volumes. For details, see “Deleting the External Volume Mapping (Delete Volume Command)” (page 99).