Compaq EVM

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Overview

ProxyHost Configuration

Required Software

Hardware and Software Considerations

PreScan and PostScan Batch Files

Subclient Considerations

Overview

Compaq Enterprise Volume Management (EVM) is a hardware-based snapshot engine and is used to create snapshots, or clones, which are then backed up by the iDataAgent. Because the backup does not occur on the production server, resources on the production server are not affected by this operation. The ProxyHost iDataAgent can be implemented into the Compaq Enterprise Volume Management (EVM) environment to conduct backup operations using the data snapshot or clone capabilities of EVM. The system uses the snapshot or clone to back up large amounts of data without using production server resources.

See ProxyHost - Application Data to see which operating systems and applications are supported for use with Compaq EVM in conjunction with the ProxyHost iDataAgent.

The diagram that follows shows a sample ProxyHost configuration in a Compaq EVM environment.

Data from the production server is distributed to virtual disks created on Compaq Storage Subsystems. During the backup the virtual disks will be snapped or cloned and the snapshot or clone will be mounted to the backup host. All of these actions will be managed by a predefined EVM job which will be executed by the PreScan process.

The ProxyHost iDataAgent is installed on the production server only. The same File System iDataAgent is installed on both the production server and the backup host. In addition, the Compaq EVM software is installed on the production server and backup host.

During a ProxyHost backup, the following sequence of events takes place:

1. The ProxyHost iDataAgent starts a backup operation.
2. The backup PreScan process initializes the EVM job that will create the snapshot or clone and mount them to the backup host.
3. During the EVM job execution, a batch file that you create will utilize CVSnaptool during the EVM Suspend/Resume phase. This will be configured using the standard EVM web tool.
4. The snapshot or clone is backed up through the backup host.

ProxyHost Configuration

The following must be done before using ProxyHost with Compaq EVM.

1. Verify that the production server and Backup Host meet the System Requirements.
2. Install the required software.
3. Review the Hardware and Software Considerations.
4. Create PreScan and PostScan Batch Files. It is important to note that the PreScan and PostScan batch files will have to be customized for each individual snapshot environment.
5. Configure subclient(s) and content. See Subclient Considerations and Subclients - SAN iDataAgents for more information.

Required Software

The following must be installed on the production server:

• ProxyHost iDataAgent and Windows File System iDataAgent - for more information and procedures, see Deployment - ProxyHost iDataAgent.

  For a clustered environment, the ProxyHost iDataAgent must be installed on the virtual node.

• The following Compaq software:
  • EVM 2.0 Agent software
  • SANworks Secure Path software
  • StorageWorks FC Switch setup for Transparent Mode
  • StorageWorks Large LUN for Windows (optional)
• For Exchange, one of the following:
  • Exchange 2000 with SP1 or higher, or
  • Exchange 2003
• For SQL:
  • SQL Server with SP1 or higher

The following must be installed on the Backup Host:

• Windows File System iDataAgent - for more information and procedures, see Deployment - Windows File System iDataAgent.
• The following Compaq software:
  • EVM 2.0 Agent software
  • SANworks Secure Path software
  • StorageWorks FC Switch setup for Transparent Mode
  • StorageWorks Large LUN for Windows (optional)

Hardware and Software Considerations

• Ensure that the Backup Host has access to the Compaq storage system.
• Ensure that the database Freeze/Thaw environment has been set up.
• Ensure that the EVM job that will create and mount the clone to the backup host has been created and tested.
• Append the System’s PATH Environment Variable for Exchange

  For CVSnaptool to successfully quiesce an Exchange server, the system’s PATH environment variable must be appended on the Exchange server to include the directory containing eseutil.exe, as follows:

  <exchange_server_install_directory>\BIN

  where <exchange_server_install_directory> is the full path and name of the Exchange install directory; for example:

  C:\Program Files\Exchsrvr\BIN

PreScan and PostScan Batch Files

ProxyHost in a Compaq EVM environment is most commonly used to back up either snapshots or clones. Before each ProxyHost backup, the snapshots or clones must be created and mounted on to the backup host. These tasks are performed by an EVM job which will be called during the PreScan phase of each backup.

On the production server, you must create a PreScan batch file containing the appropriate evmcl command to initialize the EVM job. In order for the batch file to execute successfully, you must include the full path to the evmcl command.

The database Freeze/Thaw utility, CVSnaptool, will be implemented into the EVM job as the Suspend/Resume phase. This utility will ensure that the database and the transaction log remains consistent during the snapshot.

For specific configuration information on batch files for the PreScan and PostScan phases, see the Resource Pack for sample batch files and scripts.

We recommend that you test the batch file before associating it with any subclients.

CVSnaptool

To back up applications, such as Exchange 2000 or Exchange 2003 using ProxyHost, CVSnaptool is required; it is called from PreScan and PostScan batch files.

The use of CVSnaptool ensures that file system and application metadata remain unchanged, and therefore consistent, during the backup operation. Before creating the snapshot, the ProxyHost iDataAgent using CVSnaptool ensures that any supported applications have been ordered to flush buffered data and to suspend I/O to the disk. Once the snapshot has been created, the iDataAgent signals to the application that it may resume operations. Typically, the suspension of application I/O lasts only a few seconds. Custom scripts may be created to suspend and resume your applications. Sample scripts are provided on the Resource Pack.

• Exchange 2000 or Exchange 2003
  To suspend I/O to one or more Exchange 2000 or Exchange 2003 stores, the entire Storage Group must be dismounted. ProxyHost will dismount the appropriate Storage Group(s) at the start of the Snap phase and remount them when the snapshot is ready, by invoking CVSnaptool batch files that you have created.
• SQL Server
  To suspend I/O to one or more SQL databases, cvsnaptool can quiesce each database while they stay online. Batch files can be configured to use CVSnaptool to work with the ProxyHost to automatically quiesce the SQL databases at the start of the Snap phase and restart them when the snapshot is ready.
• File System Backups
  It is not necessary to quiesce the server for a file system backup with ProxyHost. Thus, there is no need of calling CVSnaptool from a Prescan batch file.
• Other applications
  Custom scripts may be created to suspend and resume your applications in the PreSnap and PostSnap phases.

Subclient Considerations

• The PreScan batch file is included in the Pre/Post Processes of the Subclient Properties. This PreScan process of the subclient properties should point to the shell script file located on the production server or Backup Host. For procedures, see Configure a Subclient for Pre/Post Processing of Data Protection Operations.

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