Advanced – VMware Backup

Choosing Backup Types

Full Backup

Full backups provide the most comprehensive protection of data. However, full backups also consume the most amount of time and resources. To streamline the backup process, several additional backup types are available. The sections below describe the additional backup types that are available.

1. From the CommCell Console, navigate to <Client> | Virtual Server.
2. Right-click the BackupSet and click All Tasks | Backup All Subclients.

   Click Yes.

3. Select Full as backup type and Immediate to run the job immediately.

   Click OK.

4. You can track the progress of the job from the Job Controller or Event Viewer window.
5. Once job is complete, view the details of job from the Job History.

   Right-click the client computer, click View and then click View Job History.

6. Click OK.
7. You can view the following details about the job by right-clicking the job:
   • Items that succeeded during the job
   • Items that failed during the job
   • Details of the job
   • Media associated with the job
   • Events of the job
   • Log files of the job.

Incremental Backups

An incremental backup contains only data that is new or has changed since the last backup, regardless of the type. On average, incremental backups consume far less media and place less of a burden on resources than full backups.

The illustration on the right clarifies the nature of full and incremental backups. For simplicity, assume there is a file system that contains six files as represented in the figure.

Backup #1 is a full backup and therefore writes all the data, changed and unchanged, to the backup media. Backups #2 through #n-1 are incrementals and only back up those files that have changed since the time of the last backup, regardless of the type. For example, files A, B, and E changed after the full backup and were therefore backed up in Backup #2. Backup #4 backed up files A and D because both files were modified sometime after Backup #3 occurred. File F did not change; hence, it was not backed up in any of the incremental backups, but it was included in both full backups, which, by definition, back up everything.

1. From the CommCell Console, navigate to <Client> | Virtual Server | defaultBackupSet.
2. Right click the subclient and click Backup.
3. From the Backup Options dialog box, select from the following options:

   Backup Type:

   • Select Incremental.

   Backup Schedule:

   • Select Run Immediately
4. Click OK.
5. You can track the progress of the backup job from the Job Controller window.
6. When the backup has completed, the Job Controller displays Completed.

Differential Backups

A differential backup contains only the data that is new or has changed since the last full backup. Like incremental backups, differential backups, on average, consume less media and place less of a burden on resources than full backups. Differential backups are cumulative. This means that each differential backup contains all changes accumulated since the last full backup. Each successive differential backup contains all the changes from the previous differential backup.

The illustration on the right demonstrates the nature of differential backups. For simplicity, assume there is a file system that contains six files as represented in the figure.

Backup #1 is a full backup and therefore writes all the data to the backup media. Backups #2 through #n-1 are differential backups and only back up those files that changed since the time of the last full backup. For example, files A, B, and E changed after the full backup and were therefore backed up in Backup #2 as well as all subsequent differential backups. File C changed sometime after Backup #2 and was consequently backed up in Backup #3 and all subsequent differential backups. File F did not change; hence, it was not backed up in any of the differential backups, but it was included in both full backups, which, by definition, back up everything.

1. From the CommCell Console, navigate to <Client> | Virtual Server | defaultBackupSet.
2. Right click the subclient and click Backup.
3. From the Backup Options dialog box, select from the following options:

   Backup Type:

   • Select Differential.

   Backup Schedule:

   • Select Run Immediately
4. Click OK.
5. You can track the progress of the backup job from the Job Controller window.
6. When the backup has completed, the Job Controller displays Completed.

Synthetic Full Backups

A synthetic full backup is a synthesized backup, created from the most recent full backup and subsequent incremental and/or differential backups. The resulting synthetic full backup is identical to a full backup for the subclient.

Unlike full, incremental, and differential backups, a synthetic full backup does not actually transfer data from a client computer to the backup media. Therefore, they do not use any resources on the client computer.

Synthetic full backups are media-based; they read backup data from one media and simultaneously write (restore) the result to the new active media within the same media group. As a result, synthetic full backups require that at least two media drives for the same storage policy be available at the time the job is started. Synthetic full backups cannot be performed on subclients where the storage policy is associated with a stand-alone drive.

Running Synthetic Full Backups

Synthetic full backups can either be started manually or scheduled to occur at regular intervals. Do not concurrently run more than one synthetic full backup, especially synthetic full backups with multiple streams.

From the CommCell Console, navigate to <Client> | Virtual Server | defaultBackupSet. Right click the <Subclient> and click Backup. From the Backup Options window, select Synthetic Full for Backup Type. Select Immediate for Job Initiation. Click OK. You can track the progress of the backup job from the Job Controller. When the backup has completed, the Job Controller displays Completed.

Running an Incremental Backup Before or After a Synthetic Full Backup

An incremental backup can be run either before or after a synthetic full backup.

• Running an incremental backup before the synthetic full ensures that any new or recently changed data is included in the synthetic full.
• Running an incremental backup after the synthetic full ensures that any new or recently changed data since the backup that occurred prior to the synthetic full, but was not included in the synthetic full, is backed up by the incremental.

The sections below describe the steps to run an incremental backup before or after a synthetic full backup:

From the CommCell Console, navigate to <Client> | Virtual Server | defaultBackupSet. Right click the <Subclient> and click Backup. From the Backup Options window, select Synthetic Full for Backup Type. Select Run Incremental Backup and then select Before Synthetic Full or After Synthetic Full options. Select Immediate for Job Initiation. Click OK. You can track the progress of the backup job from the Job Controller. When the backup has completed, the Job Controller displays Completed.

Verifying Synthetic Full Backups

This option ensures that files that have not backed up by incremental jobs since the last full backup are backed up by the next incremental. For example: If you perform the conventional full backup only once for a given subclient and then perform incremental (or differential) backups and periodic synthetic full backups. After the conventional full backup, a file is added to the subclient and the file has a time stamp older than the time of full backup. In such scenario, the file will never get backed up. Eventually, such files may be pruned and no backup of such  files will be available. The illustration on the right explains the necessity of verifying synthetic full backups. In order to overcome this problem, it is recommended to verify the synthetic full backups job periodically as follows:

From the CommCell Console, navigate to <Client> | Virtual Server | defaultBackupSet. Right click the <Subclient> and click Backup. From the Backup Options dialog box, select Synthetic Full. Click Advanced. In the Advanced Backup Options dialog box, click the Data tab. Select Verify Synthetic Full. Click OK to continue. Click OK.

Ignoring Errors in Synthetic Full Backups

Errors encountered in synthetic full backups can be ignored, even if backup media is partially corrupted. Errors such as inability to read data (bad tape, files missing on disk media, etc.) will be ignored when this option is enabled.

From the CommCell Console, navigate to <Client> | Virtual Server | defaultBackupSet. Right click the subclient and click Backup. From the Backup Options dialog box, select Synthetic Full. Click Advanced. In the Advanced Backup Options dialog box, click the Data tab. Select Verify Synthetic Full and then select Ignore Error in Synthetic Full. Click OK to close the Advanced Backup Options dialog box. Click OK .

Accelerated Synthetic Full Backups (DASH Full)

When a storage policy copy is deduplicated, synthetic full backups can be created in an accelerated mode to significantly reduce the copy duration. This is done by identifying and transferring the data signatures (instead of the data itself) to the target wherever possible.

Scheduling A backup

1.	From the CommCell Console, navigate to Client Computers | Virtual Server Right-click the Subclient and click Backup.
2.	Click Schedule to schedule the backup for a specific time. Click Configure to set the schedule for the backup job. The Schedule Details dialog displays.
3.	Select the appropriate scheduling options.  For example: Click Weekly. Check the days you want the run the backup job. Change the Start Time to 9:00 PM Click OK to close the Schedule Details dialog Click OK to close the Backup Options dialog The backup job will execute as per the schedule.

Verifying the Virtual Machine Protection Coverage

You can get information about the number of virtual machines protected at any point in time. This information is useful to verify that all the virtual machines are getting protected as specified in the backup schedule. You can run a SQL query on the CommServe database to verify the status of backups performed for each virtual machine in the last <n> days.  When you schedule backups for a subclient, you should run this query periodically to check whether all the virtual machines are getting backed up according to the schedule.

Use the following steps to run the query:

1. Log on to the CommServe computer. Ensure that the user account used for logging in has administrative privileges.
2. Open the Microsoft SQL Server Management Studio and run the following query on the CommServe database:

    select * from VMProtectionCoverage (<n>, '<backup type>')

   where <n> is the number of days and <backup type> is the type of backup.

   For example:

    select * from VMProtectionCoverage(30,'INCR')

   This query provides the status of incremental backups performed for each virtual machine protected in the last 30 days. The query is executed for all virtual machines protected by any Virtual Server iDataAgent within the CommCell.

   To verify the status of full and incremental backups performed for each virtual machine in the last <n> days, run the query as follows:

    VMProtectionCoverage (<n>, '')

The results of the query contains the status of the backups performed for each virtual machine. The status is one of the following:

Managing Jobs

Jobs can be managed in a number of ways. The following sections provide information on the different job management options available:

Restarting Jobs

Jobs that fail to complete successfully are automatically restarted based on the job restartability configuration set in the Control Panel. This configuration can be changed at any time; however, changes to this configuration will affect all jobs run in the entire CommCell.

It is also possible to override the default CommServe configuration for individual jobs by configuring retry settings when initiating the job. This configuration, however, will apply only to the specific job.

Configure Job Restartability at the CommServe Level

1. In the CommCell Console, click the Control Panel icon, then double-click Job Management.
2. In the Job Restarts tab of the Job Management dialog box, select a job type from the Job Type list, and then select the Restartable check box.
3. To change the maximum number of times the Job Manager will try to restart a job, select a number in the Max Restarts box.
4. To change the time interval between attempts by the Job Manager to restart the job, select a number of minutes in the Restart Interval (Mins) box.
5. Click OK to save your changes.

Configure Job Restartability for an Individual Job

1. From the Backup Options dialog box, click Advanced, then select the Job Retry tab and specify the following as desired:
   • Total Running Time - The maximum elapsed time, in hours and minutes, from the time that the job is created.
   • Number of Retries - The number of times that Job Manager will attempt to restart the job.
   • Kill Running Jobs When Total Running Time Expires - Option to kill the job when the specified Total Running Time has elapsed, even if its state is "Running".
2. Click OK.

Controlling Jobs

The following controls are available for running jobs in the Job Controller window:

These controls can be applied to:

• All jobs in the Job Controller.
• All selected jobs in the Job Controller providing you have the correct security associations at the proper level for each job selected.
• All data protection operations running for a particular client or client/agent.
• All data protection operations running for a particular MediaAgent.

1. From the Job Controller of the CommCell Console, right-click the job and select Kill, Suspend, or Resume as desired.
   • When killing a job:

     Click Yes when the confirmation prompt appears if you are sure you want to kill the job. The job status may change to Kill Pending for a few moments while the operation completes. Once completed, the job status will change to Killed and it will be removed from the Job Controller window after five minutes.

   • When suspending a job:

     The job status may change to Suspend Pending for a few moments while the operation completes. The job status then changes to Suspended.

   • When resuming a job:

     As the Job Manager attempts to restart the job, the job status changes to Waiting, Pending, or Running.

Additional Options

Several additional options are available to further refine your backup operations. The following table describes these options, as well as the steps for configuring them.

Be sure to read the overview material referenced for each feature prior to using them.

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