Change the reserved capacity settings for a snapshot group

You can change the settings for a snapshot group to change its name, auto-delete settings, the maximum number of allowed snapshot images, the percentage point at which System Manager sends a reserved capacity alert notification, or the policy to use when the reserved capacity reaches its maximum defined percentage.

Before you begin

During the creation of a snapshot group, reserved capacity is created to store the data for all the snapshot images contained in the group.

Steps
  1. Select Storage  Pools & Volume Groups.

  2. Click the Reserved Capacity tab.

  3. Select the snapshot group that you want to edit, and then click View/Edit Settings.

    The Snapshot Group Settings dialog box appears.

  4. Change the settings for the snapshot group as appropriate.

    Field Details
    Setting Description

    Snapshot group settings

    Name

    The name of the snapshot group. Specifying a name for the snapshot group is required.

    Auto-deletion

    A setting that keeps the total number of snapshot images in the group at or below a user-defined maximum. When this option is enabled, System Manager 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 image limit

    A configurable value that specifies the maximum number of snapshot images allowed for a snapshot group.

    Snapshot schedule

    If Yes, a schedule is set for automatically creating snapshots.

    Reserved capacity settings

    Alert me when…​

    Use the spinner box to adjust the percentage point at which System Manager sends an alert notification when the reserved capacity for a snapshot group is nearing full.

    When the reserved capacity for the snapshot group exceeds the specified threshold, System Manager sends an alert, allowing you time to increase reserved capacity or to delete unnecessary objects.

    Policy for full reserved capacity

    You can choose one of the following policies:

    • Purge oldest snapshot image — System Manager automatically purges the oldest snapshot image in the snapshot group, which releases the snapshot image reserved capacity for reuse within the group.

    • Reject writes to base volume — When the reserved capacity reaches its maximum defined percentage, System Manager rejects any I/O write request to the base volume that triggered the reserved capacity access.

    Associated objects

    Base volume

    The name of the base volume used for the group. A base volume is the source from which a snapshot image is created. It can be a thick or thin volume and is typically assigned to a host. The base volume can reside in either a volume group or disk pool.

    Snapshot images

    The number of images created from this group. A snapshot image is a logical copy of volume data, captured at a particular point-in-time. Like a restore point, snapshot images allow you to roll back to a known good data set. Although the host can access the snapshot image, it cannot directly read or write to it.

  5. Click Save to apply your changes to the snapshot group settings.