Administrator Guide
Table Of Contents
- Dell EMC Storage Systems Administrator Guide for PowerStore and Unity XT metro node feature
- 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
- Consistency Groups
- Performance and Monitoring
- Metro node with active-passive storage arrays
- Index
Performance considerations
To improve overall metro node performance, disable automatic rebuilds or modify the rebuild transfer size:
● Disable automatic rebuilds to avoid a flood of activity when re-attaching two clusters.
CAUTION: Disabling automatic rebuilds prevents distributed RAID 1s from synchronizing. Child devices will
be out of date, increasing the likelihood of remote reads.
● Modify the rebuild transfer size. For more information, see About transfer-size.
One-time data migrations
A one-time data migration moves data between the specified source and targets as soon as you use the dm start
migration command. No reusable migration plan file is created as in Batch migrations.
Starting a one-time device migration
Steps
1. Use the drill down command to display the components of the source of a view, virtual volume, or device, down to the
storage volume level:
VPlexcli:/clusters/cluster-1> drill-down –o virtual-volumes/Symm1254_7B7_1_vol
virtual-volume: Symm1254_7B7_1_vol (cluster-1)
local-device: Symm1254_7B7_1 (cluster-1)
extent: extent_Symm1254_7B7_1
storage-volume: Symm1254_7B7
2. Identify the device used by the source storage volume.
3. Use the
ll /clusters/cluster-*/devices command to display available devices.
4. Identify an unused device as the destination.
5. Navigate to the appropriate migration context.
For device migrations, navigate to device-migration context:
VPlexcli:/> cd data-migrations/device-migrations
6. Use the dm migration start command to start a migration.
Specify the --to device by name if that name is unique in the global namespace. Otherwise, specify a full pathname.
For example:
VPlexcli:/data-migrations/device-migrations> dm migration start --name migrate_012 --
from device_012 --to device_012a --transfer-size 12M
CAUTION:
Setting a large a transfer size may result in data unavailability. Vary from the default only when
performance implications are fully understood.
If host I/O activity is high, setting a large transfer size may impact host I/O.
See About transfer-size.
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