Backup/Restore without velero dependency

[pawanpraka1]

ZFS-LocalPV has added supports for velero to do the backup and restore. But actually it is not really dependant on velero to do that. Add a steps/doc/blog to do the backup and restore without velero.

[almereyda]

If you know how this is been done, can you write a little outline naming the individual steps, that are generic and independent from Velero to you? I'm interested in seeing generic approaches to backing up PVs supported by ZFS, which are not tied to a specific vendor's application.

Also syncoid comes to mind, which is also suggested in https://github.com/openebs/zfs-localpv/issues/291#issuecomment-875740462 for an in-tree support.