HCI host template settings
HCI host templates describe models of physical hosts that support participation in a vSAN. Along with the host compute specifications, you also include specifications for storage capacity and redundancy (RAID level and failover). You can use these templates to plan for changes to your vSAN capacity.
For Hyper-V environments, if you run a Hardware Replace plan that replaces hosts with HCI Host templates, the results can be inconsistent or the plan can fail to place all the VMs in the plan scope. This typically occurs when Turbonomic detects a configuration issue with VMM or Hyper-V. As a result,Turbonomic treats the VMs as not controllable and does not attempt to place them.
The HCI Host template is a collection of these settings:
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CPU
The processor for this host model. CPU size and speed are not the only factors to determine processing power. Specify the host CPU in the following ways:
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Select from Catalog
When you enable Select from Catalog, you can open up a catalog of CPU models that Turbonomic uses to map the model to an effective capacity for the CPU.
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Cores and CPU Speed
When you disable Select from Catalog, you can specify the number of Cores and the CPU clock speed – Turbonomic multiplies these values to calculate the host CPU resources.
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Memory
The amount of memory to allocate for the VM, in GB.
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Network
The host’s network throughput, in MB/s.
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IO
The host’s IO bus throughput, in MB/s
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Storage
The capacity for this storage.
IOPS – The effective IOPS capacity.
Size – Raw storage capacity, in GB. A plan that uses this template computes the effective storage capacity.
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Redundancy
The redundancy method for this storage is on the virtualized SAN. This combines the RAID level and the number of host failures to tolerate.
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Price
If you know the price of the host model that you're specifying for the template, you can enter it here. When a plan runs, Turbonomic uses the price to calculate costs or savings when adding or removing host machines in an on-prem data center.
Selecting CPUs from the catalog
CPU processor speed is not necessarily an effective indicator of CPU capacity. For example, processor architecture can make a slower CPU have a greater effective capacity. Newer models of machines can often have fewer cores or less clock speed, but still have a higher effective capacity. Planning is affected in two ways:
When planning hardware replacement, the plan knows the template's effective capacity. The plan knows how to best place workloads on the new hardware.
For already deployed hosts, Turbonomic discovers the effective capacity and uses that information when it calculates workload placement.
To build the catalog of CPU capacity, Turbonomic uses benchmark data from spec.org. When you set up the CPU for a host template, you can search this catalog for the processor you want, and set it to the template.
Turbonomic also uses the effective processor capacity when it calculates workload placement in real-time. For more information, see Effective CPU Capacity.
