IntelliMagic Vision provides sizing and analysis capabilities for the Asynchronous Copy Services implementations from all the vendors: IBM’s Global Mirror, EMC’s SRDF/A, HP’s Continuous Access Asynchronous and Journal, and HDS TrueCopy/Async and Universal Replicator.
Bandwidth sizing based on existing data is supported for all these implementations, with analysis capabilities specific for each platform. IntelliMagic Vision uses historical data on total write throughput and translates it to network capacity requirements.
How Far Behind Could my DR Get?
With Asynchronous data mirroring, an installation can deliberately configure less bandwidth than what is needed in the peak intervals, accepting that this will have an impact on the currency of the secondary data image: the target of how far the secondary data image will run behind on the primary data image may be willingly compromised during a certain period of the day, for instance during the batch hours.
With IntelliMagic Vision for z/OS, the user can define the amount of bandwidth available and will then be presented with information about how long the secondary delay will be over target. This allows the capacity planner to see when and for how long delays would occur such that it is possible to take a well-informed decision about the bandwidth needed for this specific I/O load.
Account for Rewrites
Asynchronous data mirroring as implemented in IBM’s Global Mirror and EMC’s SRDF/A, operates in cycles. This may have an impact on the amount of bandwidth needed to mirror the data since only the last update of a record within an interval needs to be transmitted to the secondary disk subsystem. IntelliMagic Vision computes the amount of write activity (expressed in MB /sec) for those devices that will be part of the data mirroring configuration and the amount of data that would have to be transmitted.
IntelliMagic Vision is valuable for managing production Asynchronous Copy Services from IBM or EMC. For IBM customers running Globally Disbursed Parallel Sysplex (GDPS) reporting is available based on SMF type 105 records. For EMC customers running Symmetrix Remote Data Facility Asynchronous (SRDF/A) reporting is done based on SMF type 206 records.
IBM Global Mirror reporting provides guidance on the health of your replication sessions. If replication falls behind you can quickly determine root cause and act before a Global Mirror outage occurs. You can also track your Recovery Point Objective (RPO) and be sure that any Service Level Objectives are met.
EMC SRDF/A reporting also focuses on the health of the replication environment. It will show you the average and maximum cycle times and trigger an alert when thresholds are exceeded often enough. Reports on many other SRDF/A metrics such as cycle time target, cycle size, and repeat writes are also available.
Would you like to learn more?
Contact us if you would like to know more about our Asynchronous Copy Services capabilities and we are happy to show you.
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