Storage Foundation and High Availability Solutions 8.0.2 HA and DR Solutions Guide for Microsoft SQL Server - Windows
- Section I. Getting started with Storage Foundation and High Availability Solutions for SQL Server
- Introducing SFW HA and the VCS agents for SQL Server
- How is application availability achieved in a VMware virtual environment
- Notes and recommendations
- How VCS monitors storage components
- Deployment scenarios for SQL Server
- Reviewing the active-passive HA configuration
- Reviewing a standalone SQL Server configuration
- Reviewing the campus cluster configuration
- Reviewing the Replicated Data Cluster configuration
- About setting up a Replicated Data Cluster configuration
- Disaster recovery configuration
- Reviewing the disaster recovery configuration
- Notes and recommendations for cluster and application configuration
- Configuring disk groups and volumes for SQL Server
- About managing disk groups and volumes
- Configuring the cluster using the Cluster Configuration Wizard
- Installing SQL Server
- Completing configuration steps in SQL Server
- Introducing SFW HA and the VCS agents for SQL Server
- Section II. Configuring SQL Server in a physical environment
- Configuring SQL Server for failover
- About configuring the SQL Server service group
- Configuring the service group in a non-shared storage environment
- Configuring an MSDTC Server service group
- Configuring campus clusters for SQL Server
- Configuring Replicated Data Clusters for SQL Server
- Setting up the Replicated Data Sets (RDS)
- Configuring a RVG service group for replication
- Configuring the resources in the RVG service group for RDC replication
- Configuring the VMDg or VMNSDg resources for the disk groups
- Configuring the RVG Primary resources
- Adding the nodes from the secondary zone to the RDC
- Verifying the RDC configuration
- Configuring disaster recovery for SQL Server
- Setting up your replication environment
- About configuring disaster recovery with the DR wizard
- Configuring replication and global clustering
- Configuring the global cluster option for wide-area failover
- Testing fault readiness by running a fire drill
- About the Fire Drill Wizard
- Prerequisites for a fire drill
- Preparing the fire drill configuration
- Deleting the fire drill configuration
- Configuring SQL Server for failover
How application availability is achieved in a physical environment
The VCS agents continuously monitor the application, storage, and network components that the application uses in the cluster. The agents are able to detect failures in all of these components. For example, an application-level failure such as a configured application virtual server or application service becoming unavailable, a fault in the storage such as a configured disk becoming inaccessible, or a network failure.
When a fault occurs, VCS fails over the application service group to the next available system in the application service group's system list. A service group failover means that the VCS storage agents deport and import the disks or LUNs on the new system. The VCS network agents bring the network components online and the application-specific agents then start the application services on the new system.
In a disaster recovery cluster configuration, VCS first attempts to failover the application service group within the local cluster. If all the systems in the local cluster are unavailable, VCS attempts to failover the service group to a system at the remote site.
In a NetApp environment, the VCS NetApp agents perform the following actions in that order:
Connect the virtual disks (LUNs) to the target hosts (NetAppSnapDrive agent).
Perform a mirror break that enables write access to the target (NetAppSnapMirror agent).
Reverse the direction of replication by demoting the original source to a target, and begin replicating from the new source (NetAppSnapMirror agent).
If replication is set up using Volume Replicator (Volume Replicator), the Volume Replicator replication agents make the Secondary RVG at the remote site write-enabled so that it becomes the new Primary. After the storage is connected, VCS starts the application services on the new system at the remote site. The data that is replicated to the remote site is used to restore the application services to the clients.