Welcome to the Community,
you may want to take a look at http://communities.vmware.com/docs/DOC-8760 to see whether this is something you are looking for.
If not, please provides some details like VMware product used, ...
you could Veeam are offering a basic backup program now for minimal cost. You can use Vmware DataProtector to backup your vm's as this comes with vSphere and you do not have to pay for it \o/
If you do not have any budget to purchase the backup software, then you can use free vesion of Veeam B&R, which allows running backup jobs in the ad-hoc mode. Please see Veeam webiste for further details > http://www.veeam.com/virtual-machine-backup-solution-free.html