The full backup of Hyper-V 2012 R2 VM replica is working fine, but the differential and incremental backup of Hyper-V 2012 R2 VM replica is not working and it will fall back to a full backup instead.
The job has a exception as below:
A Full backup was run on this virtual machine, since the option to fall back to a full backup was selected. Incremental\\Differential backup methods are not supported for this virtual machine.
I am wondering whether it is not supported?..
It is supported. A full backup can run instead of incremental / differential for various reasons such as the VM being powered off, Hyper-V Integration services are either not installed or not updated, unsupported disk configuration of the VM, lack of sufficient free space etc.