HP StorageWorks XP External Storage user guide: HP XP12000 Disk Array, HP XP10000 Disk Array, HP 200 Storage Virtualization System (T1706-96017, June 2010)

Figure 4 Example of incorrect alternate path configurations
.
Examples of switching I/O execution paths to alternate paths
There are two alternate path modes: Single mode and Multi mode. This section describes examples
of the performance when the I/O execution path switches to the alternate path for each path mode
as follows:
• Alternate path mode is Multi mode.
• Alternate path mode is Single mode.
• Alternate path mode is Single mode and at least one alternate path is in Standby status.
For more information about path status, see Adding alternate paths by selecting multiple external LUs
(Add Paths).
• Alternate path mode is Multi mode.
Figure 5 shows an example of when the alternate path mode is Multi mode. When an error occurs
in one path, I/Os execute using paths other than the error path.
NOTE:
As you restore the error path, use of the restored path automatically resumes.
XP External Storage Software User Guide 27