Hitachi ShadowImage for IBM z/OS User"s Guide (T5213-96002, June 2007)

About ShadowImage™ for IBM
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z/OS
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Operations 2-23
Hitachi ShadowImage™ for IBM
®
z/OS
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User’s Guide
– the S-VOL status of the SIz pair if the SIz T-VOL and TCz M-VOL share
the same volume.
• ShadowImage for z/OS supports multiple T-VOLs for each S-VOL. If you
issue a pair status query to an SIz S-VOL, the status for only one SIz pair
is reported (the pair with the T-VOL with the lowest LDEV ID). To obtain
the pair status for the SIz pair(s) with the other T-VOL(s), you must direct
the host query to the specific T-VOL using the T-VOL’s LDEV ID in the host
command. The SIz remote console software displays the LDEV ID and SIz
pair status of all T-VOLs associated with an S-VOL.
• Reverse copy and quick restore operations can be performed on shared
SIz/TCz pairs only when the TCz pair is suspended.
Table 2-4 describes the host pair status reporting for SIz volumes, TCz
volumes, and SIz/TCz shared volumes.
Table 2-4 Host Pair Status Reporting for SIz/TCz Shared Volumes
Number of SIz S-VOLs Number of TCz Pairs Pair Status Reported by Storage System
0 0 Simplex
1 0 SIz pair status
2 or more 0 SIz pair status for the pair whose T-VOL has the lowest
LDEV ID
0 1 TCz pair status
1 1 TCz pair status
2 or more 1 TCz pair status
The following table lists the currency of the data on shared SIz/TCz volumes
based on the SIz and TCz pair status.
Table 2-5 Currency of a Shared SIz and TCz Volume
TCz Pair Status
SIz Pair Status Pending Duplex Suspended
Pending Not current Not current Not current
Duplex Not current Not current CURRENT
SP-Pending Not current Not current CURRENT
V-Split Not current Not current CURRENT
Split CURRENT CURRENT CURRENT
Resync Not current Not current CURRENT
Resync-r - - CURRENT
Suspended Not current Not current Not current
The configuration shown in Figure 2-10 is an example of a volume, which is
functioning as both an SIz S-VOL and a TCz M-VOL. This configuration allows
you to: