EMC VMAX 100K, Руководство по эксплуатации продукта

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The following image shows legacy mode:
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2 cycles (capture and transmit) on the R1 side, and
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2 cycles (receive and apply) on the R2 side
Figure 32 SRDF/A SSC cycle switching – legacy mode
Primary Site Secondary Site
Capture
cycle
Apply
cycle
Transmit
cycle
Receive
cycle
Capture
N
Transmit
N-1
R2
R2
Receive
N-1
Apply
N-2
R1
R1
In legacy mode, the following conditions must be met before an SSC cycle switch can
take place:
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The previous cycle’s transmit delta set (N-1 copy of the data) must have
completed transfer to the receive delta set on the secondary array.
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On the secondary array, the previous apply delta set (N-2 copy of the data) is
written to cache, and data is marked write pending for the R2 devices.
SSC cycle switching in concurrent SRDF/A
In single session mode, cycle switching on both legs of the concurrent SRDF topology
typically occurs at different times.
Data in the Capture and Transmit cycles may differ between the two SRDF/A
sessions.
SRDF/A MSC cycle switching
SRDF/A MSC:
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Coordinates the cycle switching for all SRDF/A sessions in the SRDF/A MSC
solution.
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Monitors for any failure to propagate data to the secondary array devices and
drops all SRDF/A sessions together to maintain dependent-write consistency.
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Performs MSC cleanup operations (if possible).
HYPERMAX OS
SRDF/A MSC sessions where both arrays are running HYPERMAX OS have two or
more cycles on the R1 side (multi-cycle mode).
Note
If either the R1 side or R2 side of an SRDF/A session is running HYPERMAX OS,
Solutions Enabler 8.x or later is required to monitor and manage MSC groups.
The following image shows the cycles on the R1 side (one capture cycle and multiple
transmit cycles) and 2 cycles on the R2 side (receive and apply) for an SRDF/A MSC
session when both of the arrays in the SRDF/A solution are running HYPERMAX OS.
Remote replication solutions
130 Product Guide VMAX 100K, VMAX 200K, VMAX 400K with HYPERMAX OS