Sun Cluster Geographic Edition Data Replication Guide for EMC Symmetrix Remote Data Facility

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Activating an EMC Symmetrix Remote Data Facility Protection Group

When you activate a protection group, the protection group assumes the role that you assigned to it during configuration. You can activate a protection group in the following ways:

Globally – Activates a protection group on both clusters where the protection group is configured
On the primary cluster only – Secondary cluster remains inactive
On the secondary cluster only – Primary cluster remains inactive

Activating an EMC Symmetrix Remote Data Facility protection group on a cluster has the following effect on the data replication layer:

The data replication configuration of the protection group is validated. During validation, the current local role of a protection group is compared with the configuration of the EMC Symmetrix Remote Data Facility device groups.

If the EMC Symmetrix Remote Data Facility device group is not in a Failedover state, the local role of the protection group should match the role of the EMC Symmetrix Remote Data Facility device group.

If the EMC Symmetrix Remote Data Facility device group is in a Failedover state, then the local role of the protection group becomes secondary while the role of the EMC Symmetrix Remote Data Facility device group remains primary.
Data replication is started on the data replication device groups that are configured for the protection group, no matter whether the activation occurs on a primary or secondary cluster. Data is always replicated from the cluster on which the local role of the protection group is primary to the cluster on which the local role of the protection group is secondary.

Application handling proceeds only after data replication has been started successfully.

Activating a protection group has the following effect on the application layer:

When a protection group is activated on the primary cluster, the application resource groups that are configured for the protection group are also started. The Sun Cluster Geographic Edition software uses the following Sun Cluster commands on the primary cluster to bring the resource groups online:
# scswitch -Z -g rglist
When a protection group is activated on the secondary cluster, the application resource groups are not started. The resource groups are put into the unmanaged state.

How to Activate an EMC Symmetrix Remote Data Facility Protection Group

When you activate a protection group using the command in this procedure, application resource groups in the protection group are also brought online. For details about how the -e (scope) option affects resource groups in the protection group, see the geopg(1M) man page.

Log in to a cluster node.

You must be assigned the Geo Management RBAC rights profile to complete this procedure. For more information about RBAC, see Sun Cluster Geographic Edition Software and RBAC in Sun Cluster Geographic Edition System Administration Guide.

Activate the protection group.
# geopg start -e scope [-n] protectiongroupname
-e scope

Specifies the scope of the command.

If the scope is local, then the command operates on the local cluster only. If the scope is global, the command operates on both clusters that deploy the protection group.

Note –
The property values global and local are not case sensitive.

-n

Prevents the start of data replication at protection group startup.

If you omit this option, the data replication subsystem starts at the same time as the protection group.

protectiongroupname

Specifies the name of the protection group.

The geopg start command uses the scswitch -Z -g resourcegrouplist command to bring resource groups and resources online. For more information about using this command, see the scswitch(1M) man page.

Example 2–14 How the Sun Cluster Geographic Edition Software Issues the Command to Start Replication

In this example, the Sun Cluster Geographic Edition software starts data replication of an EMC Symmetrix Remote Data Facilitydevice group.

First, the EMC Symmetrix Remote Data Facility protection group is created.

phys-paris-1# geopg create -s paris-newyork-ps -o primary -d srdf srdfpg

The device group devgroup1 is added to the protection group.

phys-paris-1# geopg add-device-group devgroup1 srdfpg

The current RDF pair state of an EMC Symmetrix Remote Data Facility device group, devgroup1, is returned in the output of the symrdf query command as follows:

phys-paris-1# symrdf -g devgroup1 query
Device Group (DG) Name             : devgroup1
DG's Type                          : RDF1
DG's Symmetrix ID                  : 000187401215


       Source (R1) View                 Target (R2) View     MODES           
--------------------------------    ------------------------ ----- ------------
             ST                  LI      ST                                    
Standard      A                   N       A                                   
Logical       T  R1 Inv   R2 Inv  K       T  R1 Inv   R2 Inv       RDF  Pair    
Device  Dev   E  Tracks   Tracks  S Dev   E  Tracks   Tracks MDA   STATE       
-------------------------------- -- ------------------------ ----- ------------

DEV001  00E4 RW       0       36 NR 00E4 RW      36        0 S..   Split       
DEV002  00E5 RW       0       36 NR 00E5 RW      36        0 S..   Split       
DEV003  00E6 RW       0       36 NR 00E6 RW      36        0 S..   Split

The aggregate device group state is Split.

Next, the protection group, srdfpg, is activated by using the geopg start command.

phys-paris-1# geopg start -e local srdfpg

The Sun Cluster Geographic Edition software runs the symrdf -g devgroup1 establish command at the data replication level. If the command is successful, the state of devgroup1 is returned in the output of the symrdf query command as follows:

phys-paris-1# symrdf -g devgroup1 query
Device Group (DG) Name             : devgroup1
DG's Type                          : RDF1
DG's Symmetrix ID                  : 000187401215


       Source (R1) View                 Target (R2) View     MODES           
--------------------------------    ------------------------ ----- ------------
             ST                  LI      ST                                    
Standard      A                   N       A                                   
Logical       T  R1 Inv   R2 Inv  K       T  R1 Inv   R2 Inv       RDF Pair    
Device  Dev   E  Tracks   Tracks  S Dev   E  Tracks   Tracks MDA   STATE       
-------------------------------- -- ------------------------ ----- ------------

DEV001  00E4 RW       0        0 RW 00E4 WD       0        0 S..   Synchronized
DEV002  00E5 RW       0        0 RW 00E5 WD       0        0 S..   Synchronized
DEV003  00E6 RW       0        0 RW 00E6 WD       0        0 S..   Synchronized

Example 2–15 Activating an EMC Symmetrix Remote Data Facility Protection Group Globally

This example activates a protection group globally.

# geopg start -e global srdfpg

The protection group, srdfpg, is activated on both clusters where the protection group is configured. The application resource groups in srdfpg are brought online on the primary cluster.

Example 2–16 Activating an EMC Symmetrix Remote Data Facility Protection Group Locally

This example activates a protection group on a local cluster only. This local cluster might be a primary cluster or a secondary cluster, depending on the role of the cluster.

# geopg start -e local srdfpg

If the local cluster is the primary cluster, the resource groups in srdfpg also brought online on that cluster.