EMC VMAX 100K, Руководство по эксплуатации продукта

Страница: 148 / 200

Figure 42 SRDF/Metro life cycle
Non-SRDF
Standard Devices
Synchronize
Synch-In-Progress
SRDF/Metro
Active/Active
SRDF createpair
establish/restore/invalidate
The life cycle of an SRDF/Metro configuration includes the following steps and states:
l
Create device pairs in an empty SRDF group.
Create pairs using the new -rdf_metro option to indicate that the new SRDF pairs
will operate in an SRDF/Metro configuration.
If all the SRDF device pairs are Not Ready (NR) on the link, the createpair
operation can be used to add more devices into the SRDF group.
l
Make the device pairs Read/Write (RW) on the SRDF link.
Use the -establish or the -restore options to make the devices Read/Write (RW)
on the SRDF link.
Alternatively, use the -invalidate option to create the devices without making them
Read/Write (RW) on the SRDF link.
l
Synchronize the device pairs.
When the devices in the SRDF group are Read/Write (RW) on the SRDF link,
invalid tracks begin synchronizing between the R1 and R2 devices.
Direction of synchronization is controlled by either an establish or a restore
operation.
l
Activate SRDF/Metro
Device pairs transition to the ActiveActive pair state when:
n
Device federated personality and other information is copied from the R1 side
to the R2 side.
n
Using the information copied from the R1 side, the R2 side sets its identify as
an SRDF/Metro R2 when queried by host I/O drivers.
n
R2 devices become accessible to the host(s).
When all SRDF device pairs in the group transition to the ActiveActive
state,host(s) can discover the R2 devices with federated personality of R1
devices. SRDF/Metro manages the SRDF device pairs in the SRDF group. A write
to either side of the SRDF device pair completes to the host only after it is
transmitted to the other side of the SRDF device pair, and the other side has
acknowledged its receipt.
l
Add/remove devices to/from an SRDF/Metro group.
The group must be in either Suspended or Partitioned state to add or remove
devices.
Use the deletepair operation to delete all or a subset of device pairs from the
SRDF group. Removed devices return to the non-SRDF state.
Use the createpair operation to add additional device pairs to the SRDF group.
Remote replication solutions
148 Product Guide VMAX 100K, VMAX 200K, VMAX 400K with HYPERMAX OS