I have a particular virtual machine which is backed up with xsidiff and xsitools. For this virtual machine, I plan to change the directory name and several file names of the related vmdk harddisk files for consistency reasons, i.e. that the directory name and vmdk harddisk files have the name of the virtual machine. ESXi supports un-registering, changing file names via vmkfstools, editing the vmx file and re-registering the modified virtual machine. This works fine.
Now I wonder what impact such renaming has on earlier backups performed with xsidiff and xsitools. We can assume that the name of the virtual machine remains the same so that xsibackup can easily assign the new file structure to the same virtual machine.
What I would expect is that the renaming does not lead to a malfunction of the backups, but to a one-time increase of backup size after having changed the file names, as the changed files will be interpreted as completely new data, while the old files do not longer exist.
Am I right with this assumption or should I be aware about further side effects that breaks the backup chain once the files have been renamed?
You don't even need vmkfstools to rename the file structure of a VM. VMWare probably advises to do so to take the chance to renew virtual disks consistency and punch zeros.
If you rename the file structure, don't even try to continue some Onediff replica, just create a new one. Same applies to XSIDiff as backing up to the same path would duplicate disks, the old and the new names would be in the same folder (not clean). In regards to XSIDiff, you can continue to use the same repository, blocks that already exist won't be created, so you should be fine continuing to backup to the same repository.