D-PST-OE-23 PowerStore Migration

PowerStore Migration Detailed Explanation

1. Overview

Migration is the process of moving data from older storage systems to PowerStore. PowerStore simplifies this through:

• Native Import tools (built into PowerStoreOS)

• Support for external and host-based migration tools

The goal is to make migration:

• Low-risk (preserve data)

• Non-disruptive (minimal downtime)

• Efficient (use automation where possible)

There are two major approaches:

• Internal Migration using PowerStore’s native import wizard

• External Migration using host tools or third-party software

This explanation focuses on native import, which is Dell's preferred method when supported.

2. Supported Migration Sources

PowerStore’s native migration tools support block-based imports from specific Dell EMC storage systems, including:

• Unity and Unity XT

• VNX and VNXe (some models)

• SC Series (formerly Compellent)

• EqualLogic (older systems)

• XtremIO (limited cases)

These are supported natively and directly discoverable by PowerStore.

For third-party storage systems, you must use:

• Host-based tools (e.g., Robocopy, rsync)

• Hypervisor-level migration (e.g., vSphere Storage vMotion)

3. Migration Prerequisites

Before starting a migration, you must ensure a few preconditions are met:

A. Compatibility Check

• Confirm that both source and destination systems use supported firmware versions.

• Reference Dell's official compatibility matrix to avoid issues.

B. Network and Zoning Configuration

• Make sure that:

  • PowerStore can communicate with the legacy storage.

  • For Fibre Channel, proper zoning must be in place.

  • For iSCSI, IQNs and IP access need to be configured.

C. Storage Resource Identification

• Identify which volumes/LUNs will be migrated.

• Validate that data is healthy and consistent.

• If possible, unmount volumes from production hosts during migration.

  • If unmounting is not possible, consider live migration strategies.

4. Migration Workflow (Block Volumes)

PowerStore offers a simple, wizard-driven method for migrating data using the PowerStore Manager GUI or REST API.

Step 1: Create a Migration Session

• Log in to PowerStore Manager.

• Choose “Import Storage”.

• Select the source system and enter credentials (if needed).

• PowerStore automatically discovers eligible volumes.

Step 2: Select and Map Source Volumes

• Choose the source volumes you want to import.

• Define target PowerStore volumes (size, name, protection policies).

• Optionally group them into volume groups.

Step 3: Initiate Import

• The migration process starts copying data in the background.

• This step is non-disruptive—the source volume continues to serve data.

• You can pause/resume the migration if needed.

Step 4: Cutover

• After all data has been copied, PowerStore alerts you that it's ready to complete.

• At this stage:

  • Access to the source volume is stopped

  • PowerStore becomes the new active storage

• This is the final step where data is officially “cut over” to PowerStore.

Step 5: Cleanup

• Optionally, unconfigure or remove the legacy storage.

• Hosts are updated to point to PowerStore volumes.

• Migration is complete.

5. File System Migration

PowerStore does not support native file system migration.

To move NAS or file share data, use:

• Robocopy (Windows)

• rsync (Linux/Unix)

• NDMP (Network Data Management Protocol) with backup software

• DobiMigrate from Dell (licensed separately)

Preserving Permissions

During file migration, it's important to preserve:

• NTFS ACLs (Windows access control lists)

• POSIX permissions (Unix-style ownership and mode bits)

Correct options must be used with rsync or Robocopy to retain these.

6. Considerations and Best Practices

A. Minimize Downtime

• If PowerStore’s native tools are not viable (e.g., unsupported source), use VMware vMotion or host-based tools to migrate live systems.

B. Performance Monitoring

• Migration can affect performance.

• Avoid high I/O periods and monitor system performance during migration.

C. Data Verification

• Always verify the data after migration:

  • Run checksums or hash comparisons

  • Validate application and database integrity

D. Logging and Rollback

• All migration sessions are logged for auditing and tracking.

• Rollback is possible only before cutover.

• After cutover, PowerStore becomes the active system.

E. Security

• Secure all data paths during migration.

• Use encryption, especially across public or shared networks.

7. When to Use External Migration Tools

Use external tools in the following cases:

• Heterogeneous migrations (e.g., moving from NetApp, HPE, or IBM)

• Application-specific needs, like database exports

• Granular file-level migration with custom scripting or ACL preservation

Common tools include:

• VMware vMotion / Storage vMotion

• Dell PowerPath Migration Enabler (PPME)

• NAS migration utilities like BoostFS, Robocopy, or rsync

Summary of PowerStore Migration

Section	Key Details
Supported Systems	Unity, VNX, SC Series, XtremIO, EqualLogic
Methods	Native import for block; external tools for file
Migration Workflow	Wizard-driven with phases: discovery, import, cutover, cleanup
File Migration Tools	Robocopy, rsync, DobiMigrate, NDMP-based backup
Best Practices	Minimize downtime, validate data, encrypt transfers, monitor performance
When to Use External Tools	For unsupported systems, advanced file migration, or specialized needs

PowerStore Migration (Additional Content)

1. Support for Parallel Migration Sessions

Can PowerStore run multiple import sessions at the same time?

• Yes, PowerStore supports parallel migration sessions, allowing multiple volumes or volume groups to be imported simultaneously.

• This feature improves overall migration throughput and is particularly useful in:

  • Large-scale enterprise environments

  • Multi-tenant configurations

  • Time-sensitive cutover windows

Performance Considerations:

• Although sessions run concurrently, total system throughput is still subject to:

  • Storage pool bandwidth

  • Source system I/O limits

  • Network capacity between source and PowerStore

Exam Relevance:

You might be asked:
“An administrator wants to migrate 10 volumes from a VNX system to PowerStore simultaneously. What is required?”
Correct answer: Parallel sessions are supported; ensure performance capacity is monitored.

2. Cross-Pool Migration Capability

Can imported volumes be placed into a different storage pool than the source system?

• Yes, PowerStore allows you to specify the destination storage pool during the import setup process.

• This gives administrators flexibility to:

  • Separate workloads by performance class (e.g., SSD vs. hybrid)

  • Align with different SLAs or organizational departments

  • Support infrastructure consolidation strategies

Important Notes:

• The destination pool must have sufficient available capacity and be online.

• Pool assignment is configured at the time of creating the target volume during import setup.

Exam Relevance:

Scenario example:
"Can an administrator import a volume from Unity and assign it to a PowerStore pool different from the default?"
Correct answer: Yes, pool selection is available during native import configuration.

3. Snapshot Support During Native Import

Is snapshot creation supported during an active migration session?

• Technically, yes, PowerStore supports snapshot operations during an import session, including:

  • Manual snapshots of the target volume

  • Scheduled snapshot policies

• However, it is not recommended to snapshot the destination volume during active data synchronization, because:

  • It may cause inconsistent point-in-time recovery if the migration is not yet complete

  • Snapshots taken mid-transfer may contain incomplete datasets

Best Practice:

• Wait until the migration session has reached cutover state before performing snapshot operations

• If necessary, perform snapshots immediately after cutover for backup and rollback purposes

Exam Caution:

A trap question might ask:
"Is it safe to snapshot a PowerStore volume during a native import process?"
Correct answer: Technically possible, but not recommended due to potential data inconsistency.

Summary Table

Topic	Key Insight
Parallel Migration Sessions	Supported; allows multi-volume imports for large-scale or multi-tenant migrations
Cross-Pool Targeting	Allowed; target pool is selectable during import session setup
Snapshots During Import	Technically allowed, but discouraged before cutover due to risk of data inconsistency