How to modify protection options
Published : April 8, 2005 | Updated : August 17, 2005
When you create a protection group, you set protection options or accept the default settings for synchronization, shadow copies, consistency checks, and network performance. After you create a protection group, you can modify these settings, as needed, to better meet your data protection requirements and optimize network performance.
Important
If you are protecting file servers in a time zone that is different from that of the DPM server, the times specified in the Modify Protection Options dialog are file server times.
Setting synchronization options
You can choose between two modes of synchronization: Only before each shadow copy is created or Nearly-continuous (hourly). If you are protecting data that changes frequently throughout the day, you may want to synchronize your data hourly. If you are protecting data that changes less frequently, you can synchronize your data only before each shadow copy is created and thereby minimize potential network performance problems related to protection activity.
To set synchronization options
In DPM Administrator Console, click Protection on the navigation bar.
In the Display pane, select the protection group for which you want to set synchronization options.
In the Actions pane, click Modify protection options.
On the Synchronization tab, select the synchronization frequency.
To apply your changes, click OK
Note
The Estimated recovery goals section of the dialog box provides estimates of the number of days for which you can maintain shadow copies and the maximum data loss you could sustain, given the shadow copy schedule that you have specified. To reduce the maximum data loss, select Nearly-continuous (hourly) synchronization frequency.
Scheduling shadow copy jobs
You can create as many as eight shadow copies of a synchronized replica within a 24-hour period.
To schedule shadow copy jobs
In DPM Administrator Console, click Protection on the navigation bar.
In the Display pane, select the protection group for which you want to set synchronization options.
In the Actions pane, click Modify protection options.
The Modify Protection Options dialog box is displayed.
On the Shadow Copy tab under Times of day, specify the times in file server time for which you want DPM to create shadow copies by using the Add and Remove buttons. DPM can create a maximum of eight scheduled shadow copies each day.
Note
Shadow copy time is not the time when DPM creates a shadow copy. Rather, it is the point in time on the file server that the shadow copy represents. To ensure that a shadow copy reflects the state of a file server at the specified shadow copy time, DPM must synchronize the replicas with the file server before it creates the shadow copy. Depending on the synchronization schedule, shadow copy creation can take place up to several hours after shadow copy time.
Under Days of the week, specify the days of the week on which you want DPM to run protection jobs by selecting and clearing their associated boxes.
To apply your changes, click OK.
Note
The Estimated recovery goals section of the dialog box provides estimates of the number of days for which you can maintain shadow copies and the maximum data loss you could sustain, given the shadow copy schedule that you have specified. To extend the number of days for which you can maintain shadow copies, consider excluding days on which you experience little change to your data — Saturdays and Sundays, for example.
Scheduling consistency checks
You may need to perform synchronization with consistency check to repair inconsistencies between the protected data on the file server and the replica on the DPM server. You can schedule a daily consistency check during off-peak hours to ensure that the replica remains consistent with the protected data. A scheduled consistency check will only run if inconsistencies are detected during synchronization. Keep in mind that the performance of the file server may be affected while the consistency check is running.
To schedule a consistency check
In DPM Administrator Console, click Protection on the navigation bar.
In the Display pane, select the protection group for which you want to set synchronization options.
In the Actions pane, click Modify protection options.
On the Consistency Check tab, check Schedule consistency check and then specify the start time and maximum number of hours to allow for the consistency check.
To apply your changes, click OK.
Setting performance options
By using the performance options DPM provides, you can minimize the impact on network performance when running protection jobs. The following table describes those options:
Option |
Description |
|---|---|
Network bandwidth throttling |
Limits the network bandwidth that DPM can use to create and synchronize replicas. |
On-the-wire compression |
Allows faster data throughput during replica creation and synchronization without negatively affecting network performance. |
Specify start times for protection jobs |
Makes it possible to manually stagger the start times for protection jobs by protection group, thereby avoiding the impact on network performance of running multiple large protection jobs simultaneously. This option is most useful when you have multiple protection groups. Note that DPM automatically staggers the start times of jobs across servers within a protection group. The protection jobs for each server are offset from one another by 10 minutes, so that the jobs of up to 6 servers are evenly distributed. If you are protecting more than 6 servers, jobs start to overlap. |
To set performance options
In DPM Administrator Console, click Protection on the navigation bar.
In the Display pane, select the protection group for which you want to modify performance options.
In the Actions pane, click Modify protection options.
To enable network bandwidth throttling, select Enable network bandwidth usage throttling and select the maximum speed for data transfers from the file servers to DPM.
To enable on-the-wire compression, select Enable on-the-wire compression.
To stagger the starting times for protection jobs, under Start protection jobs, specify the number of minutes after the hour to start synchronization and shadow copy jobs.
To apply your changes, click OK.