GDDR RDF/QAR accelerated swap sequences
AssigneeDell Products L.P.
InventorsPeter Callewaert, Dennis Trulli, Jr.
Life of this patent
Estimating the term…
Abstract
SQAR site and region swap sequences include a combination of full swap and half swap commands to avoid creating a cascaded R21 while reducing elongated RDF resume processing. This is accomplished by limiting the use of half swap commands to mirrors that do not have an RDF resume command in the affected swap sequence and that require half swap to avoid creation of a cascaded R21. Changing the replication direction for the other mirrors, if necessary in the context of a site or region swap sequence, is done using full swap commands, thus enabling fast RDF resume processing on those legs.
Claims20
An apparatus comprising:
- a geographically dispersed disaster restart data facility with quadrilateral replication comprising a first storage array in a first datacenter in a first region, a second storage array in a second datacenter in the first region, a third storage array in third datacenter in a second region, and a fourth storage array in fourth datacenter in the second region;
- the first storage array configured to maintain a R11 storage object that is synchronously replicated to a first R21 storage object maintained by the second storage array via a synchronous leg;
- the first storage array further configured to asynchronously replicate the first R11 storage object to a second R21 storage object maintained by the third storage array via a first asynchronous leg;
- the second storage array configured to asynchronously replicate the first R21 storage object to a R22 storage object maintained by the fourth storage array via a second asynchronous leg;
- the second R21 storage object maintained by the third storage array being paired with the R22 storage object maintained by the fourth storage array via a recovery leg;
- the geographically dispersed disaster restart data facility with quadrilateral replication configured to perform site swaps using a combination of replica personality half swaps and replica personality full swaps.
A method comprising:
- in a storage system comprising a geographically dispersed disaster restart data facility with quadrilateral replication comprising a first storage array in a first datacenter in a first region, a second storage array in a second datacenter in the first region, a third storage array in third datacenter in a second region, and a fourth storage array in fourth datacenter in the second region;
- configuring the first storage array to maintain a R11 storage object that is synchronously replicated to a first R21 storage object maintained by the second storage array via a synchronous leg;
- configuring the first storage array to asynchronously replicate the first R11 storage object to a second R21 storage object maintained by the third storage array via a first asynchronous leg;
- configuring the second storage array to asynchronously replicate the first R21 storage object to a R22 storage object maintained by the fourth storage array via a second asynchronous leg;
- pairing the second R21 storage object maintained by the third storage array with the R22 storage object maintained by the fourth storage array via a recovery leg;
- and
- performing site swaps using a combination of replica personality half swaps and replica personality full swaps.
A non-transitory computer-readable storage medium that stores instructions that when executed by at least one computer in a storage system including a first storage array in a first datacenter in a first region, a second storage array in a second datacenter in the first region, a third storage array in third datacenter in a second region, and a fourth storage array in fourth datacenter in the second region, perform a method comprising:
- configuring the first storage array to maintain a R11 storage object that is synchronously replicated to a first R21 storage object maintained by the second storage array via a synchronous leg;
- configuring the first storage array to asynchronously replicate the first R11 storage object to a second R21 storage object maintained by the third storage array via a first asynchronous leg;
- configuring the second storage array to asynchronously replicate the first R21 storage object to a R22 storage object maintained by the fourth storage array via a second asynchronous leg;
- pairing the second R21 storage object maintained by the third storage array with the R22 storage object maintained by the fourth storage array via a recovery leg;
- and
- performing site swaps using a combination of replica personality half swaps and replica personality full swaps.
Dependencies are inferred from the claim text.