VMware Fault Tolerance

VMware FT is a failover feature that preserves the running state of the VM, and thus provides real time backup with no loss of data or connectivity. As with DRS and HA, shared storage is required for the FT feature.

FT requires that the entire VM environment be duplicated because the memory state must be identical between the live VM and the failover VM.

This requirement might be acceptable for critical systems, but FT has severe restrictions for use with IP Availability Manager, particularly the limitation of a single vCPU for any FT-enabled VM. Because of the recommendation for a minimum of two vCPUs for an IP Availability Manager VM, the use of FT is not recommended as a failover solution for most Smarts customers.