EMC SnapView

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Overview

• ProxyHost - EMC SnapView 1.0 and 2.0 for Windows - Snapshots
• ProxyHost - EMC SnapView 2.0 for Windows - Clones

ProxyHost Configuration

• Required Software
• Hardware and Software Considerations
• PreScan and PostScan or PostBackup Batch Files
• CVSnaptool
• Subclient Considerations

QR Agent Configuration

• EMC SnapView Considerations

License Requirement

Overview

EMC SnapView is a hardware-based snapshot provider. For the Quick Recovery Agent for Windows, EMC SnapView 2.0 can be configured as the snapshot engine. Conceptually, the EMC snapshot will act as the QR Volume; the snapshot is activated during recovery. For ProxyHost, EMC SnapView is used to create snapshots, or clones (EMC SnapView 2.0 only), 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.

See ProxyHost - Application Support to see which operating systems and applications are supported for use with EMC SnapView in conjunction with the ProxyHost iDataAgent.

See Quick Recovery Agent - Application Support to see which operating systems and applications are supported for use with EMC SnapView in conjunction with the Quick Recovery Agent.

ProxyHost - EMC SnapView 1.0 and 2.0 for Windows - Snapshots

The ProxyHost iDataAgent can be implemented into the EMC SnapView system to conduct backup operations using a snapshot of the SnapView session. ProxyHost uses the snapshot to back up large amounts of data without using production server resources.

The diagram that follows shows a sample ProxyHost configuration in an EMC SnapView environment.

Data from the production server is distributed to Source LUNs created on the EMC storage systems, using the EMC Navisphere management software. During the backup the EMC SnapView sessions will be started and a snapshot of the source LUNs will be created by taking a point-in-time image. Further transactions will be written into Cache LUNs before the SnapView sessions are stopped. A SnapView session can be stopped by a batch file which runs during the PostBackup phase.

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 EMC Navisphere 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. During the PreScan process, CVSnaptool quiesces the application before the snapshot is created.
3. The PreScan process creates the snapshot.
4. CVSnaptool unquiesces the application
5. The snapshot is mounted to the backup host.
6. The snapshot is backed up through the backup host.

ProxyHost - EMC SnapView 2.0 for Windows - Clones

The ProxyHost iDataAgent can be implemented into the EMC SnapView 2.0 system to conduct backup operations using a clone of the source LUN. ProxyHost uses the clone to back up large amounts of data without using production server resources.

The diagram that follows shows a sample ProxyHost configuration in an EMC SnapView 2.0 environment using a clone.

Data from the production server is distributed to Source LUNs created on the EMC storage system, using the EMC Navisphere management software. Before the backup, either a new SnapView 2.0 clone will be created and built up or an existing clone will be synchronized. A SnapView 2.0 clone can be deactivated or removed by a batch file which runs during the PostBackup phase.

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

1. The ProxyHost iDataAgent starts a backup operation.
2. The backup PreScan process either creates a new clone, or updates an existing clone and mounts it to the backup host.
3. During the PreScan process, CVSnaptool will be executed to quiesce the application before the clone is fractured from the source, and unquiesces the application afterward.
4. The clone is backed up through the backup host.
5. The clone is either removed, requiring the creation of a new clone at the next backup, or it is deactivated, thus preserved to be updated for the next backup.

ProxyHost Configuration

The following must be done before using ProxyHost with EMC SnapView.

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. For EMC SnapView 2.0, configure the snapshot object or configure the clone group that you intend to use for backups (Refer to EMC documentation for more information).
5. Create PreScan and PostScan or PostBackup Batch Files.
6. Configure subclient(s) and content. See Subclient Considerations and Subclients - SAN iDataAgents for more information.

Required Software

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

  NOTES

  • In a clustered environment, the Windows File System iDataAgent must be installed on all of the physical nodes. Refer to Deployment - Windows File System iDataAgent.
• Navisphere Admsnap
• Navisphere Agent software
• Navisphere CLI utility
• For Exchange 2000:
  • Exchange 2000 with SP1 or higher
• For SQL Server:
  • SQL Server with SP1 or higher

The following must be installed on the Backup Host:

• Windows File System iDataAgent - for more information and procedures Deployment - Windows File System iDataAgent.
• Navisphere Admsnap
• Navisphere Agent software
• Navisphere CLI utility

Hardware and Software Considerations

Using Clones with EMC SnapView 2.0

Clones are a complete, physical copy of a volume, unlike snapshots which are a virtual copy, and as such, they use storage space. Thus there are two different strategies for backing up data with clones, either the use of addclone or syncclone in the PreScan batch file. The addclone switch is used when you do not already have a clone from a previous backup, and need to create a new, complete clone. The syncclone switch is used when you do have an existing clone from a previous backup and want to update it for the current backup. Similarly, the PostBackup batch file can either remove the clone when the backup is complete, requiring the use of the addclone switch for the next backup, or it can only deactivate the clone, storing it for use with the syncclone switch for the next backup.

Append the System’s PATH Environment Variable

On both the production server and backup host, append the system’s PATH environment variable to include <software installation path>\Base folder, where <software installation path> is the name of the directory where you installed the software.

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 or PostBackup Batch Files

ProxyHost in an EMC SnapView 1.0 environment is most commonly used to back up snapshots. Before a ProxyHost backup, the SnapView snapshot must be created. Then a session must be created for that snapshot, and the snapshot must be mounted to a backup host; these tasks are performed by a batch file which runs automatically during the PreScan phase of each backup.

ProxyHost in an EMC SnapView 2.0 environment is most commonly used to back up snapshots or clones. The scripts or batch files provided for SnapView are based on two assumptions:

• For snapshots, these script files assume that you have utilized EMC Navisphere Manager GUI to manually configure the snapshot object.
• For clones, these script files assume that you have utilized EMC Navisphere Manager GUI to manually configure the clone group.

For EMC SnapView 2.0, these two actions are not scripted because they are one-time actions. Once a snapshot object or clone group has been created, all of the additional tasks necessary to create a snapshot or clone which must be performed every time a new backup is executed, will be handled by the PreScan batch files that you create.

On the backup host, create a batch file containing the appropriate command for the type of data and platform that you want to back up. In order for the batch file to execute successfully, you must include the full path to the command.

The database Freeze/Thaw utility, CVSnaptool, will be utilized in the PreScan process. This utility will ensure that the database and the transaction log remains consistent during the snapshot. Note that it is not necessary to quiesce the server for a file system backup with ProxyHost, and thus no need to call CVSnaptool from a PreScan batch file.

It is recommended 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.

QR Agent Configuration

The following must be done before using the QR Agent with EMC SnapView 2.0.

1. Verify that the computer in which you wish to install the software satisfies System Requirements for the Quick Recovery Agent.
2. Install the required software. Note that you can de-select QSnap if you will be using EMC SnapView exclusively.
3. To use the QR Agent with the SnapView Enabler, the path of admsnap.exe (an EMC SnapView executable) must be added to the PATH environment variable on the Quick Recovery Agent client computer.
4. Configure the snapshot object in the EMC Navisphere software. A snapshot object must be configured in the EMC Navisphere application prior to configuring the QR Policy. Remember when setting up the QR Agent the primary, or source volume, contains the data you want to protect.
5. Configure a QR Policy for VSS Hardware shadows by selecting EMC SnapView as the Snapshot Engine Type. For more information see QR Policies.
6. Configure Subclient Content. The subclient should be associated with the QR Policy that is setup to use EMC SnapView. as the snapshot engine. The subclient contents should consist of the source volume for which you have created a snapshot object.

Once you have completed configuration, you can create snapshots with EMC SnapView, which can later be recovered, or activated. It is possible to activate (mount) a snapshot without performing a QR Volume recovery. A recovery will mount the snapshot to the same drive letter and LUN as the source volume, whereas activating the snapshot assigns it the next free drive letter. Activation and de-activation are performed from the Browse window of the QR Agent containing the snapshot.

Required Software

The following must be installed on the source client computer:

• Quick Recovery Agent
• SnapView Enabler for Quick Recovery (this can be installed during the install of the Quick Recovery Agent)
• The following EMC Navisphere software: 
  • Navisphere Admsnap
  • Navisphere Agent software
  • Navisphere CLI utility
• To use the Quick Recovery Agent to browse and recover QR Volumes at the application level for Exchange 2000, Exchange 2003, or SQL Server, one of the following iDataAgents must be installed: 
  • Exchange 2000 Database iDataAgent 
  • Exchange 2003 Database iDataAgent 
  • SQL Server iDataAgent

See Deployment - Quick Recovery Agent for installation instructions.

EMC SnapView Considerations

Before creating snapshots with EMC SnapView, review the following information:

• EMC SnapView can only stop the snapshot session if the original source volume is mounted. The software will not be able to delete a SnapView snapshot from the QR Browse window unless the source volume for that snapshot is mounted. This is particularly important for QR recovers, because the source volume will always be dismounted after a recover. For example, if you have 3 snapshots of a particular source volume and recover one of the snapshots, the other 2 snapshots cannot be deleted or pruned until the source volume is remounted (you can remount it to any available drive letter).
• Snapshots initiated from the QR Agent will be assigned a session number and appear in the EMC Navisphere application.
• When creating EMC SnapView snapshots, the Activate Snapshot option is available in the QR Volume Creation dialog box. Selecting this option specifies that the EMC SnapView snapshot will be activated (mounted) after creation. See QR Agent Configuration for more information.

License Requirement

To perform a data protection operation using this Agent a specific Product License must be available in the CommServe^® Server.

Review general license requirements included in License Administration. Also, View All Licenses provides step-by-step instructions on how to view the license information.

Enabler Licenses

The EMC SnapView Enabler for the Quick Recovery Agent requires a license.

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