Dell PowerVault MD3820f - Manual (Page 147)

6. Select the repository, from the Repository candidates table, that you want to use for each member
virtual disk in the consistency group.
NOTE: Select a repository candidate that is closest to the capacity you specified.
– The Repository candidates table shows both new and existing repositories that are capable of
being used for each member virtual disk in the consistency group based on the value you
specified for percentage or the value you specified for preferred capacity.
– By default, the system displays the repositories for each member virtual disk of the consistency
group using a value of 20% of the member virtual disk’s capacity. It filters out undersized
repository candidates, and those with different Data Service (DS) attributes. If appropriate
candidates are not returned using these settings, you can click Run Auto-Choose to provide
automatic candidate recommendations.
– The Difference column shows the mathematical difference between your selected capacity and
the actual capacity of the repository candidate. If the repository candidate is new, the system uses
the exact capacity size that you specified and displays zero (0) in the Difference column.
7. To edit an individual repository candidate:
a) Select the candidate from the Repository candidates table and click Edit to modify the capacity
settings for the repository.
b) Click OK.
8. Select View advanced options and then accept or change the following default settings as
appropriate.
For more information on the advanced settings, see the online help topics.
9. Click Finish.
Changing Snapshot Group Settings
Use the Snapshot Group Change Settings option to modify the auto-delete settings and the snapshot
group repository settings that were configured when you created the snapshot group.
• Auto-Delete Settings — You can configure each snapshot group to keep the total number of
snapshot images in the group at or below a user-defined maximum. When this option is enabled, the
system automatically deletes the oldest snapshot image in the group, any time a new snapshot is
created, to comply with the maximum number of snapshot images allowed for the group.
• Snapshot Group Repository Settings — You can define a maximum percentage for the snapshot
group repository that determines when a warning is triggered when the capacity of a snapshot group
repository reaches the defined percentage. In addition, you can specify which policy to use when the
capacity of the snapshot group repository reaches its maximum defined percentage:
– Automatically purge oldest snapshot image — The system automatically purges the oldest
snapshot image in the snapshot group, which releases the repository’s reserve space for reuse
within the snapshot group.
• Reject writes to base virtual disk: When the repository reaches its maximum defined percentage, the
system rejects any I/O write request to the base virtual disk that triggered the repository access.
1. From the AMW, select the Storage & Copy Services tab.
2. From the snapshot groups category node, select the snapshot group that you want to change and
then select Copy Services → Snapshot Group → Change Settings.
The Change Snapshot Group Settings window is displayed.
3. Change the snapshot group settings as required.
4. Click OK to apply your changes to the snapshot group.
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