Help
Table Of Contents
- Dell EMC Storage Systems Online Help for the metro node appliance
- Contents
- Figures
- Welcome
- Using the GUI
- Configuring GUI default settings
- Using storage hierarchy maps
- Viewing system status
- Monitoring the system
- Performance
- The Performance Monitoring dashboard
- Viewing a chart
- Modifying a dashboard layout
- Creating a custom dashboard
- Removing a chart
- Moving a chart
- Back-end Bandwidth Chart
- Back-end Throughput chart
- Back-end Errors chart
- Back-end Latency chart
- CPU utilization chart
- Heap Usage chart
- Front-end Queue Depth chart
- Front-end Bandwidth chart
- Front-end Latency chart
- Front-end Throughput chart
- Front-end Aborts chart
- Write Latency Delta chart
- WAN Port Performance chart
- WAN Latency chart
- Rebuild Status dashboard
- Virtual Volumes dashboard
- Front End Ports dashboard
- System Health
- Performance
- Provisioning storage
- Guide
- Provisioning from storage volumes
- Provision Job properties
- Distributed storage
- Storage arrays
- Storage volumes
- Devices
- About devices
- Using the Devices view
- The Create Devices wizard
- The Add Local/Remote Mirror wizards
- Viewing the status of IO to a device
- Creating a device
- Renaming a device
- Deleting a device
- Mirroring a device
- Device status
- Device component properties
- Device properties
- Distributed device properties
- Add capacity to virtual volumes
- Extent properties
- Extents
- Distributed devices
- About distributed devices
- The Distributed Devices view
- The Create Distributed Device from Claimed Storage Volumes wizard
- Distributed device rule sets
- Changing the rule set for a distributed device
- Creating a distributed device
- Deleting a distributed device
- Renaming a distributed device
- Distributed Device status
- Virtual volumes
- About virtual volumes
- The Virtual Volumes view
- The Distributed Virtual Volumes view
- Creating a virtual volume
- About virtual volume expansion
- Expanding a virtual volume using storage volumes
- Enabling or disabling remote access for a volume
- Manually assigning LUN numbers to volumes
- Deleting a volume
- Renaming a volume
- Tearing down a volume
- Virtual Volume status
- Pool properties
- Virtual volume properties
- Show ITLs dialog box
- Logical unit properties
- ALUA Support field values
- Visibility field values
- Extent or Device mobility job properties
- Metro node port properties
- Storage array properties
- Storage view properties
- Storage volume properties
- Create Virtual Volumes dialog box
- Consistency group
- About consistency groups
- Using the Consistency Groups view
- Distributed Consistency Groups view
- Create Consistency Group wizard
- Types of consistency groups
- Creating a consistency group
- Adding a volume to a consistency group
- Removing a volume from a consistency group
- Deleting a consistency group
- Consistency Group status
- Consistency group properties
- Step 1: Select or create a consistency group for the virtual volume
- Step 1: Create a consistency group
- Step 2: Select volume options
- Step 3: Select a storage pool
- Step 3: Select a pool for each mirror on the second cluster
- Step 3: Select a pool for each mirror in the cluster
- Step3: Create thin virtual volumes
- Select a storage view for the virtual volume(s) (optional)
- Step 5: Review your selections
- Step 6: View results
- Step 2: Select volume options
- Step 2: Select volume options
- Step 3: Select a storage volume to create the virtual volume
- Step 3: Select a source and target storage volume
- Step 3: Create thin volumes
- Step 3: Select a target storage volume on the remote cluster
- Step 3: Select target storage on the remote cluster
- Step 6: View results
- Show Logical Units
- Exporting storage
- Initiators and metro node ports
- Storage views
- About storage views
- Using the Storage Views screen
- The Create Storage View wizard
- Creating a storage view
- Deleting a storage view
- Renaming a storage view
- Adding or removing initiators from a storage view
- Adding virtual volumes to a storage view
- Removing virtual volumes from a storage view
- Adding or removing metro node ports from a storage view
- Storage view status
- Storage group properties
- Director properties
- Cluster properties
- Moving data
- Mobility
- Move Data Within Cluster
- Move Data Across Clusters
- Create Mobility Job wizards
- Mobility job transfer size
- Creating a mobility job
- Viewing job details
- Committing a job
- Canceling a job
- Pausing a job
- Resuming a job
- Removing the record of a job
- Changing a job transfer size
- Searching for a job
- Mobility job status
- Notifications
● Check for bandwidth or IOPS over-provisioned metro node front-end ports. Be sure to balance hosts and LUNs across
the available directors and front-end ports presented from metro node. Check the front-end fabric for saturation or over-
capacity.
● Verify that front-end Fibre Channel ports, HBAs, and switch ports are configured to the proper port speeds.
● For your host multipathing software, configure them based on metro node best practices, and make sure the installed
software versions are compatible with metro node (see the Simple Support Matrix for metro node document, available on
Dell EMC Online Support.)
Corrective actions (metro node Metro only)
● For metro node Metro configurations, check the inter-cluster link health and maximum performance capabilities. From the
metro node Management GUI, check the observed inter-cluster WAN bandwidth. If your application throughput appears low
to you, and only seems to achieve something similar to what the WAN bandwidth reports, then chances are you are limited
by the WAN. Therefore:
○ Ensure you have provisioned enough inter-cluster bandwidth for the desired application workload. Verify that your WAN
configuration is supported by metro node (minimum supported bandwidth, supported inter-cluster latency, compatible
WAN hardware and software).
○ If using Fibre Channel devices over dark fibre or DWDM, confirm that you have allocated enough buffer credits or
configured the Fibre Channel WAN ports properly on your switches. Check for buffer credit starvation, c3 discards, and
CRC errors. Some vendors may require extended fabric licenses to enable WAN features.
○ Validate your WAN performance before going live in production. Create multiple test distributed-devices and force them
to rebuild. Observe the performance of the rebuilds.
○ When troubleshooting distributed device performance, if feasible, check local device performance. Export a test LUN
from your storage array to metro node, then to the host, and then run a test I/O workload.
○ Check for any unexpected local or distributed rebuilds or data migrations. There will be some amount of performance
impact to host application traffic that relies on the same virtual volumes and storage volumes. Tune the rebuild transfer-
size setting using the CLI to limit rebuild/migration performance impact. Consider scheduling migrations during off-peak
hours.
Changing the view
Use the following appropriate selection criteria to filter the data:
● Director — Allows you to select all directors or a specific director in the cluster.
● Read and Write check boxes — Allows you to select one or both check boxes to filter bandwidth for Reads and Writes.
Viewing the Front-end Bandwidth chart
1. From the GUI main menu, click Performance.
2. In the Performance Dashboard, select the tab in which you want to display the Front-end Bandwidth chart (or create a
custom tab).
3. Click +Add Content.
4. Click the Front-end Bandwidth icon.
Front-end Latency chart
The Front-end Latency chart on the Performance Dashboard provides details of the front-end I/O latency statistics for your
metro node system.
Front-end latency is defined as the amount of time an I/O spends within metro node. The reported metro node front-end
latency should match closely to the host or application reported latency, unless there is significant added delay in the front-end
fabric, HBA, multi-pathing software, or host operating system software.
It is important to distinguish how front-end latency write operations behave in the two metro node configurations:
● For metro node Local write operations, it includes the time spent protecting the disk blocks to one or more local storage-
arrays.
● For metro node Metro write operations, it includes the time spent protecting the disk blocks to the storage-array at BOTH
clusters. When writing to the remote cluster, the round-trip time on the WAN links adds to the front-end latency, depending
upon the observed network delay between clusters.
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Monitoring the system