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rushdirizvygmai
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vSphere 6.5 FT Limitations

Hi Gurus,

VMware FT has limitations. Where number of FT vm's per host and maximum vCPU's aggreagated across host is limited.

Can these be adjusted? If so what's maximum that can be adjusted to?

das.maxftvmsperhost - The maximum number of fault tolerant VMs allowed on a host in the cluster. Both Primary VMs and Secondary VMs count toward this limit. The default value is 4.

das.maxftvcpusperhost - The maximum number of vCPUs aggregated across all fault tolerant VMs on a host. vCPUs from both Primary VMs and Secondary VMs count toward this limit. The default value is 8.

Thanks,

Rushdi

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rcporto
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Not sure about the maximum number and the impact of change that to a value higher than the default, but according with the following VMware KB article you can even disable that limit using the value 0 (zero), see: vSphere High Availability error messages (2146276) | VMware KB

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Richardson Porto
Senior Infrastructure Specialist
LinkedIn: http://linkedin.com/in/richardsonporto
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Gavis4569
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It will depend on the workload of VMs and your network connectivity.

Those default limitations are "fail-safe". So basically you will be OK with whatever (supported) configuration of VMs.

If you go higher then the IO workload of the VM kicks in. There will be large difference between enabling FT on higly utilized Exchange / SQL servers vs. some web application server for example.

Martin Gavanda https://martingavanda.com https://learnvmware.online