The Failure to Tolerate (FTT) in vSAN is a functionality that allows users to set redundancy in a vSAN cluster based on your failure domain. In the case of a physical component failure, FTT allows your VM to continue to have access to your data through copies.
For further information on understanding Failures to Tolerate (FTT) in vSAN, visit:
https://bit.ly/3RJAQEx
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