Hi, forwarding Sofia's response from a recent thread [1]. Check out this explanation [2]. [1] https://lists.openstack.org/pipermail/openstack-discuss/2023-May/033818.html [1] https://web.archive.org/web/20160404120859/http://gorka.eguileor.com/inside-cinders-incremental-backup/?replytocom=2267 Zitat von garcetto <garcetto at gmail.com>: > good morning, > i was trying cinder-backup to backup cinder volumes from nfs backend and > ceph rbd backend. > both my test show that i can do incremental cinder-backup, but i dont get > how technically the cinder-backup could "understand" the new incremental > blocks from previous backup? > maybe on ceph it leverages ceph-diff? > but on nfs backend, how it knows changed blocks? > > thank you