Dell PowerVault MD3260 Administrator's Guide - Page 101
Preparing Host Servers To Create The Snapshot Using The Advanced Path
View all Dell PowerVault MD3260 manuals
Add to My Manuals
Save this manual to your list of manuals |
Page 101 highlights
• Capacity Allocation - This parameter allows you to choose where to create the snapshot repository virtual disk. You can allocate capacity by using one of the following methods: - Use free capacity on the same disk group where the source virtual disk resides. - Use free capacity on another disk group. - Use unconfigured capacity and create a new disk group for the snapshot repository virtual disk. - It is recommended placing the snapshot repository virtual disk within the disk group of the source virtual disk. This ensures that if drives associated with the disk group are moved to another storage array, all the virtual disks associated with the snapshot virtual disk remain in the same group. • Snapshot Repository Virtual Disk Capacity - The snapshot repository virtual disk capacity is expressed as a percentage of the source virtual disk capacity. The maximum percentage allowed is 120 percent. • Percent Full-When the snapshot repository virtual disk reaches the user-specified repository full percentage level, the event is logged in the Major Event Log (MEL). The default snapshot repository full percentage level is 50% of the source virtual disk. • Snapshot Repository Virtual Disk Full Conditions - Choose whether to fail writes to the source virtual disk or fail the snapshot virtual disk when the snapshot repository virtual disk becomes full. • Host-to-Virtual Disk Mapping - Choose whether to map the snapshot virtual disk to a host or host group now or to map the snapshot virtual disk later. The default setting is Map later. Preparing Host Servers To Create The Snapshot Using The Advanced Path • Before using the Snapshot Virtual Disks Premium Feature in a Microsoft Windows clustered configuration, you must first map the snapshot virtual disk to the cluster node that owns the source virtual disk. This ensures that the cluster nodes correctly recognize the snapshot virtual disk. • Mapping the snapshot virtual disk to the node that does not own the source virtual disk before the Snapshot enabling process is completed can result in the operating system mis-identifying the snapshot virtual disk. This, in turn, can result in data loss on the source virtual disk or an inaccessible snapshot. • For details on mapping the snapshot virtual disk to the secondary node, see the documentation on storage arrays with Microsoft Windows Server Failover Clusters at support.dell.com/manuals. The destination of a snapshot repository virtual disk is determined based on the free capacity available in the disk group. A snapshot repository virtual disk requires a minimum of 8 MB free capacity. You can choose your preferred creation path-simple or advanced-if the disk group of the source virtual disk has the required amount of free space. If 8 MB of free capacity is not available in the disk group of the source virtual disk, the Create Snapshot Virtual Disks feature defaults to the advanced path. See Creating A Snapshot Virtual Disk Using The Advanced Path. NOTE: You can create concurrent snapshots of a source virtual disk on both the source disk group and on another disk group. Before creating a Snapshot Virtual Disk, note that: • The following types of virtual disks are not valid source virtual disks: - Snapshot repository virtual disks - Snapshot virtual disks - Target virtual disks that are participating in a virtual disk copy NOTE: Virtual Disk Copy is an Advanced (Premium) feature. • You cannot create a snapshot of a virtual disk that contains unreadable sectors. • You must satisfy the requirements of your host operating system for creating snapshot virtual disks. Failure to meet the requirements of your host operating system results in an inaccurate snapshot of the source virtual disk or the target virtual disk in a virtual disk copy. 101