I’ve been casting around for something to backup both the paid and free versions of ESXi 5.x VM for the least possible cost. Here is a list of the various ones I have come across. Note that I haven’t tried most of these yet so have not real comments.
Qantum vmPRO & DXi V1000 … http://www.quantum.com/products/vmbackup/vmprosoftware/index.aspx
ESXi paid version only.
Cloudbacko … http://www.cloudbacko.com/en/index.jsp
ghettoVCB … https://communities.vmware.com/docs/DOC-8760
XSIBackup … http://33hops.com/xsibackup-help-man-page.html
Another forum post … https://communities.vmware.com/thread/435152?start=15&tstart=0
Thinware vBackup … http://www.thinware.net/Products/ThinwarevBackup/tabid/202/Default.aspx
VSquare … http://www.vsquarebackup.com/#