When you activate a protection group, the protection group assumes the role that you assigned to it during configuration. When you deactivate a protection group, its application resource groups are also unmanaged.
You can activate or deactivate a protection group in the following ways:
Globally – Activates or deactivates a protection group on both clusters where the protection group is configured.
On the primary cluster only – Secondary cluster remains inactive.
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 Geographic Edition framework uses the following Oracle Solaris Cluster command on the primary cluster to bring the resource groups online:
# clresourcegroup online -eM resource-group-list
On the secondary cluster only – Primary cluster remains inactive.
When you activate a protection group, the data replication product that you are using determines the clusters on which data replication can start. The following sections describe additional behaviors when you activate or deactivate a particular data replication product.
Activating and deactivating protection group on a cluster has the following effect on the data replication layer:
When activated, 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 SRDF device groups.
If the EMC SRDF device group is not in a Failedover state, the local role of the protection group should match the role of the EMC SRDF device group.
If the EMC SRDF device group is in a Failedover state, then the local role of the protection group becomes Secondary while the role of the EMC SRDF device group remains Primary.
Data replication is started on the data replication device groups that are configured for the protection group, regardless of 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.
Deactivating an EMC SRDF 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 the protection group is compared with the aggregate device group state. If validation is successful, data replication is stopped.
Data replication is stopped on the data replication device groups that are configured for the protection group, regardless of whether the deactivation occurs on a primary or secondary cluster.
Deactivating an EMC SRDF protection group has the following effect on the application layer:
When a protection group is deactivated on the primary cluster, all of the application resource groups configured for the protection group are stopped and unmanaged.
When a protection group is deactivated on the secondary cluster, the resource groups on the secondary cluster are not affected. Application resource groups that are configured for the protection group might remain active on the primary cluster, depending on the activation state of the primary cluster.
The EMC SRDF command that is used to stop data replication depends on the RDF state of the EMC SRDF device group.
If the state is Synchronized or R1Updated, the symrdf split command is run.
If the state is Split, Suspended, Partitioned, or Failover, no command is run because no data is being replicated.
This section provides the following information:
Effects of Activating a Hitachi TrueCopy or Universal Replicator Protection Group
Effects of Deactivating a Hitachi TrueCopy or Universal Replicator Protection Group
When you activate a protection group, the protection group assumes the role that you assigned to it during configuration. For more information about activating a protection group, see Activating a Protection Group in Oracle Solaris Cluster 4.3 Geographic Edition Installation and Configuration Guide.
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 a Hitachi TrueCopy or Universal Replicator 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 aggregate device group state as described in Figure 3, Table 3, Commands Used to Start Hitachi TrueCopy or Universal Replicator Data Replication. If validation is successful, data replication is started.
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.
When a protection group is activated on the secondary cluster, the application resource groups are not started.
The Hitachi TrueCopy or Universal Replicator command that is used to start data replication depends on the following factors:
Aggregate device group state
Local role of the protection group
Current pair state
If a protection group has a consistency group defined, the fence level is async and the device group is in SMPL state, then you create the device group with the paircreate command when the geopg start command is run with the -f flag . If a protection group has a consistency group defined, the fence level is not async and the device group is in SMPL state then you create the device group with the paircreate command when you run the geopg start command with the -fg flags.
On arrays that only support the Hitachi TrueCopy software, the -fg fence level option to the geopg command is not supported. Thus, on such arrays, the user should only define the ctgid on the protection group, if that protection group only has device groups of fence level async.
The following table describes the Hitachi TrueCopy or Universal Replicator command that is used to start data replication for each of the possible combinations of factors. In the commands, dg is the device group name and fl is the fence level that is configured for the device group.
You can deactivate a protection group on the following levels:
Globally – Deactivates a protection group on both clusters where the protection group is configured
On the primary cluster only – Secondary cluster remains active
On the secondary cluster only – Primary cluster remains active
Deactivating a Hitachi TrueCopy or Universal Replicator 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 the protection group is compared with the aggregate device group state as described in Figure 4, Table 4, Commands Used to Stop Hitachi TrueCopy or Universal Replicator Data Replication. If validation is successful, data replication is stopped.
Data replication is stopped on the data replication device groups that are configured for the protection group, whether the deactivation occurs on a primary or secondary cluster.
Deactivating a protection group has the following effect on the application layer:
When a protection group is deactivated on the primary cluster, all of the application resource groups that are configured for the protection group are stopped and unmanaged.
When a protection group is deactivated on the secondary cluster, the resource groups on the secondary cluster are not affected. Application resource groups that are configured for the protection group might remain active on the primary cluster, depending on the activation state of the primary cluster.
The Hitachi TrueCopy or Universal Replicator command that is used to stop data replication depends on the following factors:
Aggregate device group state
Local role of the protection group
Current pair state
The following table describes the Hitachi TrueCopy or Universal Replicator command used to stop data replication for each of the possible combinations of factors. In the commands, dg is the device group name.
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Some replication mechanisms can only start or stop replication from the primary site. As such, for data replication to start or stop, activate or deactivate a protection group in one of the following ways:
Locally from the primary cluster
Globally from either the primary or the standby cluster
So, if you attempt to activate the protection group locally from the standby cluster, data replication does not start. However, if you activate the protection group globally from the standby cluster, data replication does start.
This applies to the following replication mechanisms:
Oracle Data Guard
ZFS Storage Appliance replication
Availability Suite