Administrator Guide
Table Of Contents
- Dell EMC Storage Systems Administrator Guide for the metro node appliance
- Contents
- Preface
- CLI Workspace and User Accounts
- Meta Volumes
- System Management
- Thin support in metro node
- Provisioning Storage
- Volume expansion
- Data migration
- About data migrations
- Migrating thin-capable storage
- About rebuilds
- One-time data migrations
- Batch migrations
- Prerequisites
- Creating a batch migration plan
- Checking a batch migration plan
- Modifying a batch migration file
- Starting a batch migration
- Pausing/resuming a batch migration (optional)
- Canceling a batch migration (optional)
- Monitoring a batch migration’s progress
- Viewing a batch migration’s status
- Committing a batch migration
- Cleaning a batch migration
- Removing batch migration records
- Configure the WAN Network
- Cluster Witness
- Consistency Groups
- Performance and Monitoring
- Metro node with active-passive storage arrays
Dual-legged RAID 1
Figure 3. Common geometries: dual-legged RAID 1
Storage-volume expansion method prerequisites
In order to expand a device or add a target for expansion using the storage-volume expansion method, the metro node virtual
volume geometry must meet one of the following criteria:
● The virtual volume is mapped 1:1 to the underlying storage volume.
● The virtual volume is a multi-legged RAID 1 volume, and each of its smallest extents is mapped 1:1 to a back end storage
volume.
● Volume geometry is a combination of any of the geometries listed previously.
Plan for volume expansion
List the expandable-capacity attribute (in the CLI) or the Expandable By field (in Unisphere) to plan capacity of your
back-end storage devices.
● expandable-capacity/Expandable By — For virtual volumes that can be expanded using the storage volume
method of expansion, this value is the capacity added to the back-end storage volume, but not yet exposed to the host by
the virtual volume.
This capacity is available for expanding the metro node virtual volume using the storage-volume method of expansion.
○ 0 (zero) - A value of zero indicates that there is no expandable-capacity for the volume. Refer the expansion-method
attribute to determine if storage volume based expansion is supported.
○ Non-zero value - A non-zero value indicates capacity available to expand the metro node virtual volume. Examine the
expansion-method attribute to determine if storage volume based expansion is supported.
Volume Expansion
Perform volume expansion using one of the following techniques:
● The virtual-volume expand CLI command.See the CLI Guide for the metro node for detailed information about this
command.
● Expand a virtual volume using the Unisphere. See the Online Help for the metro node for complete steps.
During volume expansion, using the storage-volume method, ensure that:
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Volume expansion