Figure 51 Metrocluster Topology using SDRF/Asynchronous

Data replication can utilize any extended SAN devices that support SRDF Links, for example DWDM, Fiber Channel over Internet Protocol, etc. However, since the network for a Serviceguard cluster heartbeat requires a “Dark Fiber” link, it is recommended to utilize the DWDM links for SRDF/Asynchronous data replication. This will increase data replication bandwidth and reliability in the Metrocluster environment.

Configuring Metrocluster with EMC SRDF using SRDF/Asynchronous

The following sections, “Building a Device Group for SRDF/Asynchronous”, and “Package Configuration using SRDF/Synchronous or SRDF/Asynchronous” describe the steps for building a device group and package configuration in an SRDF/Asynchronous environment.

Building a Device Group for SRDF/Asynchronous

To perform an operation on a device group for SRDF/Asynchronous data replication, the device group must be configured with all the devices that are SRDF/Asynchronous capable within the RDF group. Use the following steps to create a device group:

1.List SRDF/Asynchronous capable devices on the source Symmetrix unit and be sure the SRDF/Asynchronous capable devices are mapped to RDF group for use. In addition, all RDF devices that belong to the RDF (RA) group must be configured in one device group for SRDF/Asynchronous operation. For example, use the following command to display the devices from RDF (RA) group number 5:

#symrdf -sid symid list -rdfa -rdfg 5

Symmetrix ID: 000187400684

Local Device View

-------------------------------------------------------------------------

 

 

 

STATUS

MODES

 

 

RDF

S T A T E S

Sym

 

RDF

---------

-----

R1 Inv

R2 Inv ----------------------

 

 

 

Dev

RDev

Typ:G

SA RA LNK

MDA

Tracks

Tracks Dev RDev Pair

---- ----

------

--------- ----- -------

------- --- ---- -------------

0196

0012

R1:5

RW RW RW

S..

0

0

RW

WD

 

Synchronized

0197

0013

R1:5

RW RW RW

S..

0

0

RW

WD

 

Synchronized

0198

0014

R1:5

RW RW RW

S..

0

0

RW

WD

 

Synchronized

0199

0015

R1:5

RW RW RW

S..

0

0

RW

WD

 

Synchronized

019A

0016

R1:5

RW RW RW

S..

0

 

0

RW

WD

Synchronized

019B

0017

R1:5

RW RW RW

S..

0

 

0 RW

WD

Synchronized

292 Building Disaster Recovery Serviceguard Solutions Using Metrocluster with EMC SRDF