Starting with 8.0 Update 2 support for the option “None – Stretched Cluster” in your storage policy for a vSAN Stretched Cluster configuration has been removed. The reason for this is that it was leading to a lot of situations where unfortunately customers mistakenly had used this option and during failure realized that some VMs were not working anymore. The reason the VMs stopped working is because with this policy option objects all components of an object were placed within a single location, but there was no guarantee that all objects of a VM would reside in the same location. So you could for instance end up in the following situation shown below, where you have the VM running in Site B, with a data object stored in Site A and a data object stored in Site B, and on top of that the witness in Site B. This unfortunately for some customers resulted in strange behavior if there was an issue with the network between Site A and Site B.
Hopefully that explains why this option is no longer available.
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