EMC - VNX - LUN Migration

LUN Migration is an important feature for use in storage system tuning. LUN Migration moves data from a source LUN to a destination LUN (of the same or larger size) within a single storage system. This migration is accomplished without disruption to applications running on the host. LUN Migration can enhance performance or increase disk utilization for the changing business needs and applications by allowing the user to change LUN type and characteristics, such as RAID type or size (Destination must be the same size or larger), while production volumes remain online. LUNs can be moved between Pools, between RAID Groups, or between Pools and RAID Groups.

When a Thin LUN is migrated to another Thin LUN, only the consumed space is copied. When a Thick LUN or Classic LUN is migrated to a Thin LUN, the space reclamation feature is invoked and only the consumed capacity is copied

• LUN migration allows data to be moved from one LUN to another, regardless of RAID type, disk type, LUN type, speed and number of disks in the RAID group or Pool, with some restrictions. The process involved in the migration is the same across all VNX systems.

• The LUNs used for migration may not be private LUNs, nor may they be in the process of binding, expanding or migrating.

• Either LUN, or both LUNs, may be metaLUNs, but neither LUN may be a component LUN of a metaLUN.

• The destination LUN may not be part of SnapView or MirrorView operation. This includes Clone Private LUNs, Write Intent Log LUNs, and Reserved LUN Pool LUNs.

Note the Destination LUN is required to be at least as large as the Source LUN, but may be larger

The LUN Migration feature is transparent to any host accessing the Source LUN, though there may be a performance impact.
Copying of data proceeds while the Source LUN is available for read/write access, and the copy process may be terminated at any time. Once all data is copied, the Destination LUN assumes the full identity of the Source LUN, and the Source LUN is destroyed as a security measure. If the migration is terminated before completion, the source LUN will remain accessible to the host, and the destination will be destroyed as a security measure.
The host accessing the Source LUN sees no identity change, though of course the LUN size may have changed. In that case, a host utility, such as Microsoft Windows diskpart, can be used to make the increased space available to the host OS.

In the systems drop-down list on the menu bar, select a system. Select Storage > LUNs > LUNs. Navigate to the LUN that will be the source LUN for the migration operation, and right-click Migrate

The “Start Migration” menu option configures and starts the LUN migration operation.
If the destination LUN does not belong to the SP that owns the source LUN, the destination LUN will be trespassed to the SP that owns the source LUN before the migration starts.

• Source LUN Name: Identifies the source LUN that will be participating in the migration operation.

• Source LUN ID: Identifies the source LUN ID (iSCSI) or the WWN (Fibre Channel).

• Source LUN Capacity: Identifies the capacity of the source LUN, for example, 5 GB.

• Migration Rate: Sets the rate at which the data will be copied - valid values are Low, Medium, High, or ASAP.

Available Destination LUNs: Lists LUNs that are available to be destination LUNs. These LUNS must be the same size or larger than the source LUN

Useful Link

EMC VNX – LUN migration using VNX Snapshot

EMC VNX: LUN migration & provisioning using NAVISECCLI

LUN migration process

EMC VNX – LUN MIGRATION

EMC VNX VNX2 Technical Update - Deep Dive

Overview Link

Virtual VNX: Overview, Architecture & Use Cases

VNX Overview

Vnx series-technical-review

EMC VNX Unified Best Practices For Performance:Applied Best Practices Guide

NAS Meets SAN – an intro to VNX Unified

EMC VNX Monitoring and Reporting