HP XP Racks - Manual (Page 129)

For details about creating an inter-control unit logical path that is dedicated to the command device,
see
“Creating an inter-control unit logical path dedicated to the command device ” (page 138) .
Acquiring path information from a storage system
You can acquire the logical path information registered in a storage system in the following
situations:
•
When you want to acquire the logical path information currently defined in the storage system
•
When you want to control, or acquire information for, logical paths other than those for the
defined ports
•
When you need to know the port number to create a path set definition even though a path
has been established
To acquire path information from a storage system, do the following:
1.
Load the path set definition file by executing the YKLOAD command with the PATH parameter
specified.
2. Acquire the logical path information defined in the storage system by executing the YKQRYPTH
command with the RESTRUCT parameter specified.
NOTE: Consider the following situations that can result from executing the YKQRYPTH
command before using this functionality:
•
If the YKQRYPTH command is executed with the RESTRUCT parameter specified, path
information for the direction that is not defined in the path set definition is also acquired.
•
If the YKQRYPTH command is executed without the RESTRUCT parameter specified, path
information for the direction that is not defined in the path set definition is not acquired.
•
If the YKZ278W message is output when the YKQRYPTH command is executed, the port
number or the number of paths are different for the path set definition file and the path
information defined in the storage system.
3. Update the path set definition file with the information defined in the storage system by
executing the YKSTORE command.
The following circumstances determine the outcome of this procedure:
•
If physical path information is not defined in the storage system for the logical path for which
path information is acquired, the path set definition for that logical path is not updated.
•
If information cannot be acquired due to an I/O error, the path set definition is not updated.
•
If information can be acquired, the path set definition is updated, regardless of the status of
the physical path.
Checking the prerequisite conditions for acquiring a port number
Before you attempt to acquire the port number information from a storage system, make sure that
all of the following conditions are met:
•
A logical path has already been established between the devices to be defined.
For an inter-control logical path, a logical path must have been established between the
storage system IDs (SSIDs) defined in the path set. ◦
◦ For an inter-disk controller logical path, a logical path with the proper path group IDs
must already be established between the storage systems defined in the path set.
•
The disk configuration definition files have already been created for both the source and
destination sites between which the logical path is to be established.
•
The information required for the Remote DKC Control function is already defined.
Creating a logical path 129