HP 3PAR Application Software Suite for Microsoft Hyper-V - Manual (Page 103)

Synchronous Long Distance
The following table explains the feature of SLD (Synchronous Long Distance):
Synchronous Long Distance
Recovery Manager leverages the VSS framework to freeze the I/O at the application level and to take point in
time snapshots.
For SLD remote copy groups, the RVC (Remote Virtual Copy) creation and VC timestamp retention in local and remote
RMH servers, depends upon target storeserv selected during RVC creation. If the target storeserv having Synchronous
relationship with the source is selected, the behavior is same as that of synchronous remote copy groups and if the
target storeserv having periodic relationship with the source is selected, the behavior is same as that of periodic remote
copy groups.
NOTE: For SLD remote copy groups, RMH does not create Remote Virtual copies for the Synchronous and Periodic
target LUNs simultaneously. Remote Virtual Copy creation for the target LUN depends upon the type(sync/async
periodic) selected.
Support for Remote Copy modes and policies
Recovery Manager supports Remote Copy in synchronous and periodic mode.
•
For periodic Remote copy groups, the time based policies specified in the local RMH server
is applied to the remote virtual copies created for the target LUNs. Any modification to the
policy done during RVC creation is applied only to that particular remote virtual copy in the
target array for that creation command.
•
For synchronous Remote copy groups, the time based policies specified in the local RMH
server is applied to both the local and remote virtual copies created for source and target
LUNs respectively. Any modification to the policy done during RVC creation is applied only
to those particular to both local and remote virtual copies for that creation command.
Support for Failover Cluster for Microsoft Windows
Recovery Manager for Hyper-V supports the use of both Remote Copy and HP 3PAR Failover
Cluster Software for Microsoft Windows:
•
When synchronous mode Remote Copy is used with HP 3PAR Recovery Manager for Hyper-V
and Failover Cluster, you can use Recovery Manager to create virtual copies on both the
production system (the Remote Copy primary system) and the Remote Copy backup system.
•
When SLD Remote Copy is used with HP 3PAR Recovery Manager for Hyper-V and Failover
Cluster, you can use Recovery Manager to create virtual copies on all three systems: the
production system (the Remote Copy primary system), the synchronous mode Remote Copy
backup system, and the Periodic mode Remote Copy backup system.
NOTE:
•
Local snapshots are generated with the interference of VSS and Hyper-V VSS writer. Hence,
local snapshots are application-consistent (if it is child VM snapshot). But on remote site, there
is no such VSS or Hyper-V VSS writer involvement. Hence, remote side snapshots cannot be
guaranteed as application—constistent, but crash—consistent.
•
In remote copy group, keep VV name length less than 12. If VV name is required to be longer
than 11 characters, names shall not start with the same characters. For example, If the VV
name RMHRCVVNAME1 has to be changed, any change made after 11 characters will not
reflect the change. The change has to be made as 1RMHRCVVNAME.
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