HP StorageWorks XP Remote Web Console Software - Manual (Page 9)

Table 3 Compatibility of Volumes Shared by Version 1 and Security Solutions (continued)
Version 1 Attribute Solutions
T-VOL S-VOL
This attribute can be set. This attribute can be set. Read/Write
This setting can be made. This setting can be made. Security setting that disables
use as T-VOL Volume Security
This setting can be made. This setting can be made. External Volume HP XP External Storage
Software
External volumes are the volumes in the external storage system that are mapped as internal
volumes. For details about XP External Storage and external volumes, see the HP XP24000/XP20000
External Storage Software User Guide.
If an external volume is specified as a Version 1 T-VOL, set the time of the path blockade watch
to be less than the time set for the S-VOL of the Missing Interrupt Handler (MIH) timer on the host
side.
•
Path blockade watch is defined as the time that is set to elapse from the moment when the
external storage system is disconnected to when the path to the T-VOL is blocked.
•
MIH is a timeout period allowed for I/O requests issued by an operating system to and is
defined as the time that is set to allow S-VOL processing to complete on the host side.
CAUTION: If an MIH occurs on the S-VOL, and the path blockade watch is set to be greater than
the MIH, then if the external storage system is powered off or a power failure occurs, processing
may end abnormally.
•
If the host I/O to the S-VOL is more important than the host I/O to the T-VOL, make sure that
the time of the path blockade watch for the T-VOL is smaller than the time of the MIH timer
that is set for the S-VOL. The Version 1 relationship will be suspended when the T-VOL is
blocked because of the path blockade watch. This ensures that the host I/O to the S-VOL will
be maintained.
•
If the host I/O to the T-VOL and the T-VOL data is more important than the host I/O to the
S-VOL, use the default setting of the path blockade watch for the external volume that is to be
specified as the T-VOL.
Using Version 1 with ShadowImage for Mainframe
Version 1 allows you to add a second layer of Version 1 relationships onto the first layer of the
original ShadowImage for Mainframe pairs. These two layers of pairs (L1 and L2) allow you to
create up to six copies of one original ShadowImage for Mainframe S-VOL.
(page 10) shows an example of combining Version 1 and ShadowImage for Mainframe pairs in
the L1 and L2 pairs.
Interoperability with Other Products and Functions 9