Looking at the following table, we are using exactly the same figures, but we have also selected Datastore disk space to be included as a container for capacity management. This has had quite a dramatic effect on the capacity remaining score, as we are now down to 2.5% remaining capacity (or 2 VMs, based on disk space):
Used |
Average VM Usage |
Total Capacity |
Used Capacity |
Remaining Capacity |
|
CPU |
Yes |
3.0 GHz |
560.0 GHz |
300.0 GHz |
260.0 GHz (46.4%) |
Memory |
Yes |
7.0 GB |
800 GB |
700 GB |
100 GB (12.5%) |
Disk I/O |
No |
2.6 MBps |
760 MBps |
260 MBps |
500 MBps (65.7%) |
Network I/O |
No |
3 Mbps |
20,000 Mbps |
300 Mbps |
19,700 Mbps (98.5%) |
Disk space |
Yes |
195 GB |
20.0 TB |
19.5 TB |
500 GB (2.5%) |
Initially, your immediate thought might be, "Well this container should be enabled or else we are excluding important data from the capacity calculations". However, this all varies based on the target environment and what principals are in place.
In most environments, unless you are provisioning all your SAN storage to your vSphere clusters upfront, the total capacity value for Disk Space is misleading as your storage administrators provision new LUNs as required. This is because what the total capacity is to a vSphere administrator, is actually used/allocated capacity to a SAN administrator. In most cases, vRealize Operations has no actual visibility of how much unallocated storage remains on the physical array.
Now, there are exceptions to this example, such as pre-allocating all your storage to vSphere clusters or using a technology such as VSAN, where one large pool of storage is simply created at creation time. However, generally, you will need to rely on a partner solution pack such as EMC Analytics to provide the capacity data metrics required to properly analyze the storage array. As such, you would disable the Disk Space container at the vCenter Adapter layer and enable % Free FAST VP Pool capacity at the EMC Analytics Adapter layer.