HP StorageWorks XP Remote Web Console Software - Manual (Page 59)

External Storage XP user guide 59
• Backoff: The external disk array replied Backoff. The status of the path is Waiting because a
temporary error occurred in the external disk array’s volume. The primary path does not change
to the alternate path in this status. After the error recovery, the status becomes Normal. If the
status cannot be recovered from the error, the path status changes to the other status.
• I/O TOV: Specified timeout value regarding I/O to the external LU
• Qdepth: Number of Read/Write commands that can be issued (queued) to an external LU at one
time
• Path Watch: Time until the path to be blocked after the connection to the external disk array has
been down
• Mode: How the local disk array manages alternate paths when defined. There are two possible
values:
• Multi: Use several ports (alternate paths) at one time to distribute the workload. That is, the
external array contains Symmetrical Active/Active controllers (for example, XP).
• Single: Use only one port for one operation. If selected, the second-highest priority alternate
path is enabled only if a maintenance operation or failure affecting the primary path occurs.
That is, the external array contains Active/Passive (for example, MSA) or Asymmetrical
Active/Active controllers (for example, Hitachi 9500V).
• Previous and Next buttons
If you select several external LUs in the Device List in the LU Operations pane, click Previous to change
the Alternate Path list to the external LU appearing just above the currently displayed LU. Click Next to
change the Alternate Path list to the external LU appearing just below the currently displayed LU.
• OK button
Closes the Path Setting window, and returns to the LU Operation pane. Contents specified in the Path
Setting window appear in blue italics in the Device List, and settings appear in the Preset list.
• Cancel button
Cancels all alternate path setting operations, closes the Path Setting window, and returns to the LU
Operation pane.
Defining alternate paths
1. In the External Storage XP operations window, click LU Operation. The LU Operation pane appears.
2. Select the external LU group number in the Device Tree (left pane).
Information about the external LU mapped as an internal XP LDEV appears in the Device List (right
pane).
3. In the Device List, select the external LU, right-click, and select Path Setting.
The Path Setting window appears. The Configured Paths table in the Alternate Path list displays
detailed information about one currently defined path. The Available Paths table displays paths that
can be set as alternate paths.
4. Select the row of the path to be defined as an alternate path in the Available Paths table in the
Alternate Path list, right-click, and select Add.
The selected path is defined as an alternate path, and detailed information appears in the Configured
Paths table of the Alternate Path list.
5. Click OK in the Path Setting window.
The Path Setting window closes, and the LU Operation pane appears.
Selected rows appear in blue italics in the Device List. Specified contents also appear in the Preset list.
To check details on intended operations, select the setting in the Preset list, right-click, and select Detail.
To cancel settings, select the setting in the Preset list, right-click, and select Delete.
6. Click Apply in the LU Operation pane. A confirmation message appears.
7. Click OK.
The alternate path defined in the Path Setting window is applied to the local disk array, and specified
contents appear in the Device List.
If errors occur during alternate path operations, failed settings appear in the Preset list, and error codes
appear. To check error messages, select the failed setting, right-click, and select Detail.