InfoScale™ 9.0 Disaster Recovery Implementation Guide - Linux
- Section I. Introducing Storage Foundation and High Availability Solutions for disaster recovery
- About supported disaster recovery scenarios
- About campus cluster configuration
- About replicated data clusters
- About global clusters
- VCS global clusters: The building blocks
- About global cluster management
- About serialization - The Authority attribute
- Planning for disaster recovery
- About supported disaster recovery scenarios
- Section II. Implementing campus clusters
- Setting up campus clusters for VCS and SFHA
- About setting up a campus cluster configuration
- About running a fire drill in a campus cluster
- About setting up a campus cluster configuration
- Setting up campus clusters for SFCFSHA, SFRAC
- Setting up campus clusters for VCS and SFHA
- Section III. Implementing replicated data clusters
- Configuring a replicated data cluster using VVR
- Configuring a replicated data cluster using third-party replication
- Section IV. Implementing global clusters
- Configuring global clusters for VCS and SFHA
- Setting up VVR replication
- Creating a Replicated Data Set
- Creating a Primary RVG of an RDS
- Adding a Secondary to an RDS
- Changing the replication settings for a Secondary
- Synchronizing the Secondary and starting replication
- Starting replication when the data volumes are zero initialized
- Configuring clusters for global cluster setup
- Configuring service groups for global cluster setup
- Configuring a global cluster with Storage Foundation Cluster File System High Availability, Storage Foundation for Oracle RAC, or Storage Foundation for Sybase CE
- Configuring the secondary site
- Configuring global clusters with VVR and Storage Foundation Cluster File System High Availability, Storage Foundation for Oracle RAC, or Storage Foundation for Sybase CE
- Setting up replication on the primary site using VVR
- Setting up replication on the secondary site using VVR
- Configuring Cluster Server to replicate the database volume using VVR
- Configuring global clusters for VCS and SFHA
- Section V. Reference
- Appendix A. Sample configuration files
- Sample Storage Foundation for Oracle RAC configuration files
- About sample main.cf files for Storage Foundation (SF) for Oracle RAC
- About sample main.cf files for Storage Foundation (SF) for Sybase ASE CE
- Appendix A. Sample configuration files
About thin storage reclamation and VVR
Thin storage helps you optimize your array capacity by allocating storage to applications only when it is needed. When files are created and written to in the file system, storage is allocated from a free storage pool on the array.
However, when you delete files on the host, the storage is not automatically returned to the pool. The result is large amounts of allocated storage on the array that is now unused. You must reclaim this storage manually.
See Determining if a thin reclamation array needs reclamation.
In a VVR environment, you can reclaim storage on volumes configured under an RVG. You can reclaim storage at the disk, disk group, or file system level.
Thin storage reclamation is only supported for LUNs that have the thinrclm attribute. VxVM automatically discovers LUNs that support thin reclamation from thin-capable storage arrays. On the host, you can list devices that have the thinonly or thinrclm attributes.
Thin storage reclamation is not supported on volumes in an RVG that has full instant or space-optimized snapshots that are associated to it. The reclaim command may complete without an error, but the storage space is not reclaimed. Thin storage reclamation is not supported as reclamation on the volume triggers a data transfer from the primary volume to the snapshot volume. Moving this data to the snapshot volume triggers storage allocation at the backend. If there are multiple snapshots, copies of the same data are maintained, which requires more storage than reclaimed. In the case of space-optimized snapshots, the cache object size increases as it copies all the reclaimable data to the space-optimized snapshot.
If you have used Storage Foundation thin storage reclamation in another context, the commands are identical when you use it in a VVR environment.
When you use thin reclamation with VVR, keep in mind the following:
The VxFS file system must be mounted on the Primary site before you can perform thin reclamation on the volume.
When you reclaim storage on the Primary site, it is automatically reclaimed on the Secondary site - unless the Primary site is in DCM mode or when autosync is running. The Primary site goes into DCM mode when its SRL overflows.
You can reclaim storage on the Primary and Secondary sites even if the sites use different types of arrays. The arrays can have different fixed size physical storage allocation units.
You can reclaim storage during a rolling upgrade with no impact on your systems.
For detailed information on thin storage, as well procedures for reclaiming thin storage, see Veritas InfoScale™ Solutions Guide.