Hitachi TAGMASTORE MK-90RD011-25 - Manual (Page 52)

34 Chapter 2 Overview of CCI Operations
OLTP (DB) server DSS server
Primary
PSUS
Secondary
PSUS
R/W R/W
SMPL SMPL
R/W
c
Pair splitting
(Simplex)
e
Pair generation
(Remote)
Secondary
COPY
Primary
COPY
R/W
R/W
d
unmount
Secondary
COPY
Primary
COPY
W (Database flushing)
h
Event waiting (PSUS)
g
Restoration request c
Database freezing
d
Pair splitting
e
Database unfreezing
i
mount -r
Secondary
PAIR
Primary
PAIR
R/W
f
Event waiting (PAIR)
Secondary
PSUS
Primary
PSUS
R/W R
Secondary
COPY
Primary
COPY
R/W
differential data
Swapping paired
volume
Figure 2.16 Restoring S-VOL to P-VOL in Split Status Using ShadowImage
Note: When a swap of the primary/secondary is performed, only one paired volume is
possible.