In the Storage Cluster function, volumes that are targets of a failover are called "TFOV".
Among TFOVs created on both the Primary Storage and the Secondary Storage, those TFOVs that have the same Host Logical Unit (HLU) number and capacity are volumes whose data is synchronized. In addition to data synchronization, the volume information on the Secondary Storage is changed as shown in "Table 9.5 Change in Volume Information on Pre- and Post-Data Synchronization Secondary Storage".
Volume Information | Pre-Data Synchronization | Post-Data Synchronization |
|---|---|---|
UID | UID unique to volume on the Secondary Storage | UID of volume on the Primary Storage of a pair |
Product ID | Product ID unique to the Secondary Storage | Product ID of the Primary Storage of a pair |
Note
Even if a volume on the Secondary Storage is removed from the synchronized volume by the operation of deleting the TFO group after data has been synchronized, post-data synchronization volume information is inherited. For this reason, when continuing to use the volume on the Secondary Storage, use the ETERNUS CLI to return the volume information to pre-data synchronization status. Refer to the ETERNUS Disk storage system manuals for the command name and the format of ETERNUS CLI used.
There is an upper limit for the total capacity of all TFOVs per storage device. Refer to the following sections for the procedure to expand the total capacity of TFOVs per storage device.
When operating a TFO group with the Active-Active configuration: "Expanding Total Capacity of TFOVs" in "9.3.1 Installation"
When operating a TFO group with the Active-Standby configuration: "Expanding Total Capacity of TFOVs" in "9.4.1 Installation"
Point
The capacity of a TFOV can be expanded. Refer to the following sections for details.
When operating a TFO group with the Active-Active configuration: "9.3.2.5 Expanding Business Volume Capacity"
When operating a TFO group with the Active-Standby configuration: "9.4.2.4 Expanding Business Volume Capacity"
Required Conditions for TFOV
Volumes that are to be TFOVs must satisfy all the following conditions:
There should be volumes of the same size in respective Primary and Secondary ETERNUS Disk storage systems.
They are not the volumes used for the Non-disruptive Storage Migration.
The External LU Information of those volumes is not "Inherited".
"Veeam" is not displayed in the Usage column in the screen of Web Console for the volumes.
When an ETERNUS DX S6 series is used, Deduplication and Compression are disabled for the volume.
When operating a TFO group with the Active-Active configuration, volume type is any of "Standard", "WSV", or "TPV". In addition, the volume type of corresponding volumes on the Primary Storage and the Secondary Storage should be the same.
"SDV", "SDPV", and "FTV" are not supported.
When operating a TFO group with the Active-Standby configuration, volume type is any of "Standard", "WSV", "TPV" or "FTV". In addition, the volume type of corresponding volumes on the Primary Storage and the Secondary Storage should be the same.
"SDV" and "SDPV" are not supported.
For "FTV", synchronizing the access status data can inherit the performance information and the relocation status of Automated Storage Tiering even after failover/failback. Refer to "Access Status Data Synchronization" in the Storage Cruiser Operation Guide for Optimization Function for the method to synchronize access status data.
When operating a TFO group with the Active-Active configuration, a volume that is not concatenated with LUN concatenation.
Advanced Copy should not be in operation.
The total capacity of business volumes per storage device should not exceed the total capacity of TFOVs.
Note
The volume that belongs to the pair of CA ports cannot be shared from the unused port by the Storage Cluster function.
