"This script performs backups of virtual machines residing on
servers using methodology similar to VMware's VCB tool. The script takes snapshots of live virtual machines, backs up the master VMDKs and then upon completion, deletes the snapshot until the next backup. The only caveat is that it utilizes resources available to the Service Console of the ESX server running the backups as opposed to following the traditional method of offloading virtual machine backups through a VCB proxy."
You can find more information about the script here.