HP StorageWorks XP24000 for FlashCopy Mirroring Software User's Guide (T5240-96001, June 2007)

side, an MIH may occur on the S-VOL and the processing may end abnormally when the external

subsystem 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 that is set for the T -VOL is sm aller than the time of the MIH timer set

for the S-VOL. In this way, the Version 1 relationship 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 m aintained.

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 for the path blockade watch for the external volume that is to

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 pa irs (L1 and L2) allow you to create up to six

copies of one original ShadowImage for Mainframe S-VOL.

Figure 2 on page 18 shows an example of combining Version 1 and ShadowImage for Mainframe

pairs in the

L1 and

L2 pairs.

S-VOL

T-VOL

Legend

: Root volume

: Node volume

(L1 S-VOL and L2 T-VOL)

: Leaf volume

(L2 T-VOL)

: SIz L1 pair(The volume that is not F-Copy status)

: Version 1 L2 relationship (The volume which status is F-Copy)

Figure 2 Possible C ombination of Version 1 and ShadowImage for Mainframe Pairs

Notes

• You cannot add a Version 1 L2 relationship onto a Version 1 L1 relationship.

• You cannot add a third layer (L3 pair) onto a Version 1 L2 relationship or a ShadowImage for

Mainframe L2 pair.

• If th

L2 pair is in F-Copy status, you can only suspend o r delete the ShadowImage for Mainframe

pair.

About

Version 1 Operations