Backup From Host or Client

I have to VMs running Windows Server 2012 R2. Should I configure the backup from the host, i.e. the host does the backup? Or should I configure the backup on the client, i.e. the VM back itself up? I guess the later might require an external drive for each VM but the former only needs one. With the host backing up the VMs I assume I can still restore individual VMs rather than having to restore all of them.