[libvirt] live migration copy-storage-all , inc

Hi all, I am currently doing live migration task KVM/qemu based virtual machine I want to know what is exact difference between following: copy-storage-all option and copy-storage-inc option what are necessary steps for doing both? as per my knowledge 'copy-stoarage -all' migrates whole disk image to destination where 'copy-storage-inc' is when we use backing files for guest . with copy-storage-inc we require backing image on both destination and source but I want to know how destination guest get its base image how they share base image? Is there any link need to be created for this base image? or is there need for NFS ? How to set up both options ? what are necessary steps need to follow before starting migration ? Please help me! Regards Pankaj Rawat DISCLAIMER: ----------------------------------------------------------------------------------------------------------------------- The contents of this e-mail and any attachment(s) are confidential and intended for the named recipient(s) only. It shall not attach any liability on the originator or NECHCL or its affiliates. Any views or opinions presented in this email are solely those of the author and may not necessarily reflect the opinions of NECHCL or its affiliates. Any form of reproduction, dissemination, copying, disclosure, modification, distribution and / or publication of this message without the prior written consent of the author of this e-mail is strictly prohibited. If you have received this email in error please delete it and notify the sender immediately. . -----------------------------------------------------------------------------------------------------------------------