EMC Symmetrix DMX-3, Product Manual

Page: 237 / 326

Supported mainframe features 237
Mainframe Features and Support
The SDM then determines the timestamp of the most recent I/O from
each control unit in the session. Once these timestamps are
determined, SDM selects the smallest of these timestamps as a
starting point and forms a group that includes all I/Os received at
that time or prior. This set of I/Os constitutes a consistency group that
is written to the journal data sets, and then written to the volumes at
the recovery site. This is shown in
Figure 55 on page 237 .
Note: Only Enginuity level 5772 supports XRC functionality. Contact your
EMC Sales Representative for specific details regarding your Symmetrix
system’s support for XRC.
Figure 55 XRC overview
Configuring CKD
volumes Enginuity level 5772 supports mapping and unmapping CKD
volumes. This capability is necessary because deleting mainframe
capacity cannot take place if the volumes cannot be unmapped from a
front-end port.
Sysplex
timer
Session1 SF:
Session2 SF:
CU0
CU1
CU2
SDM(s)
Journal
State
Control
Prim a ry s ide
S econd a ry s ide
V1,T4,R3
V2,T2,R2
V2,T8,R5
…
V3,T0,R1
V3,T1,R6
…
Vol002
s cndry
Vol00 3
s cndry
Vol001
s cndry
S YM-000477
Vol001
prim a ry
Vol002
prim a ry
Vol00 3
prim a ry
z/O S
z/O S
z/O S
z/O S
z/O S
z/O S
z/O S