68 | Dell EMC VxRail Appliance Operations Guide
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Figure 37: Enabling Virtual SAN Performance Service for vSAN cluster
Once the service has been enabled, vSAN performance data is collected. You can display
graphs can in the Performance > Monitor view when a cluster, host or VM is selected in the
vCenter server inventory.
Viewing vSAN performance metrics
vSAN performance metrics are available at the cluster, host, or virtual machine level. Activity is
shown from a front-end or backend prospective.
Virtual SAN - Virtual Machine Consumption
shows front-end IO activity of the virtual machines.
Virtual SAN - Backend
shows activity for
vSAN to physical disk.
To illustrate the two different views, consider a virtual machine with a SPBM Failure Tolerance
Method of mirroring (RAID-1) that performs 200 write per second. The front-end shows 200
write IOPS, while the backend displays 400 write IOPS because (with mirroring) there are two
replicas of the data.
A top-down approach is typically used when monitoring and analyzing systems, starting at the
cluster level and working down through the ESXi hosts to the individual virtual machines. Use
cluster-level metrics on the front-end to monitor the overall system health and for capacity
management and planning. Use these metrics to understand the normal workload of the system
and to identify trends that can help determine when it is appropriate to add additional resources.
Host-level metrics includes additional data at the disk group and physical disk level. These
metrics are useful in understanding workload balance and for more detailed troubleshooting. VM
level information is used to understand the normal behavior of an application and for
troubleshooting.
The figure below shows vSAN cluster level metrics for front-end activity.
Summary of Contents for VxRail Appliance
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