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
Availability is critical for meta-volumes. The meta-volume is essential for system recovery. The best practice is to mirror the
meta-volume across two or more back-end arrays to eliminate the possibility of data loss. Choose the arrays that mirror the
meta-volume so that they are not required to migrate simultaneously.
WARNING: Do not create meta-volume using volumes from a single storage array. Single array meta-volumes are
not a high availability configuration and are a single point of failure.
If metro node temporarily loses access to all meta-volumes, the current metadata in cache is automatically written to the
meta-volumes when access is restored.
If metro node permanently loses access to both meta-volumes, it continues to operate based on the metadata in memory.
Configuration changes are suspended until a new meta-volume is created.
NOTE: If the metro node loses access to all meta-volumes, and all directors either fail or restart, changes made to the
metadata (the metro node configuration) after access was lost cannot be recovered. System volumes are supported on
thinly provisioned LUNs, but these volumes must have thin storage pool resources available, at maximum capacity. System
volumes must not compete for this space with user-data volumes in the same pool.
Moving a meta-volume
Steps
1. Use the ll command to display a list of storage volumes on the cluster:
VPlexcli:/> ll /clusters/cluster-1/storage-elements/storage-volumes
2. Identify 2 storage volumes that are:
● Unclaimed
● 78 GB or larger
● On different arrays
3. Use the meta-volume create command to create a new meta-volume.
Specify the storage volumes identified in step 2.
VPlexcli:/clusters/cluster-1/directors> meta-volume create --name meta_dmx --storage-
volumes VPD83T3:6006016037202200966da1373865de11,
VPD83T3:6006016037202200966da1373865de12
4. Use the meta-volume move command to move the existing in-memory metadata to the new meta-volume:
VPlexcli:/clusters/cluster-1/directors> meta-volume move --target-volume meta_dmx
12
Meta Volumes