Hitachi ShadowImage for z/OS user guide (HIT9503-96004, June 2006)

ShadowImage for z/OS user guide 115
Combining Compatible Mirroring for IBM® FlashCopy® Version 2 With CC
The following table shows combination of the volumes when you use FlashCopy® Mirror Version 2 with
CC.
Combining Compatible Mirroring for IBM FlashCopy Version 2 With Other Solutions
The following table shows whether you can or cannot set attributes to the volumes in the case the volumes
that are specified as S-VOL or T-VOL of a FlashCopy Mirror Version 2 pair have the attributes of Volume
Retention Manager or Volume Security.
NOTE: If an external volume is specified as a FlashCopy Version 2 T-VOL, be careful about the setting of
the time of path blockade watch, which is the time from when the external disk array is disconnected to
when the path is blocked. If the time of path blockade watch set for the T-VOL is longer than the time of the
MIH (Missing Interrupt Handler) timer which is set for the S-VOL on the host side, MIH may occur on the
S-VOL and the processing may end abnormally when the external disk array is powered off or when
failures occur.
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
path blockade watch for the T-VOL is smaller than the time of the MIH timer which is set for the S-VOL. In
this way, the FlashCopy Version 2 pair will be suspended when the T-VOL is blocked because of the path
blockade watch, therefore the host I/O to the S-VOL can be maintained.
If the host I/O to the T-VOL and the T-VOL data are 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.
FlashCopy
Mirror Version 2
CC
P-VOL S-VOL
S-VOL OK OK
T-VOL NO NO*
*Do not share FlashCopy® Mirror Version 2 T-VOL with CC S-VOL. If a T-VOL
(S-VOL) is shared by both FlashCopy® Mirror Version 2 and CC, the data in the
T-VOL (S-VOL) will be overwritten by the two programs and will be destroyed.
Table 55 Compatibility of Volumes Shared by FlashCopy Mirror Version 2 and Security Solutions
Solutions Attribute FlashCopy Mirror Version 2
S-VOL T-VOL
Volume Retention
Manager
Protect This attribute cannot be set. This attribute cannot be set.
Read only This attribute can be set. This attribute can be set.
Read/Write This attribute can be set. This attribute can be set.
Volume Security Security setting that disable
the use as S-VOL
This setting can be made. This setting cannot be made.
External Storage
XP
External storage This setting cannot be made. This setting can be made.