Hello, On Tue, 3 Jan 2017 11:16:27 +0000 许雪寒 wrote: > Hi, everyone. > > I’m researching the online backup mechanism of ceph, like rbd mirroring and multi-site. And I’m a little confused. Why is there no data backup mechanism in the rados layer? Wouldn’t this save the bother to implement a backup system for every higher level feature of ceph, like rbd and rgw? > > Thank you:) > Firstly, probably the same reasons RGW and RBD mirrorring are set up the way they are, that is asynchronously to avoid huge latency penalties. And thus tricky on the RADOS level in a generic AND selectable fashion. I.e. you may NOT want to mirror your whole cluster over that puny 1Gb/s link. Secondly, what you're talking about is HA, redundancy and replication, NOT backup. A backup system should if anyhow possible not involve Ceph at all, to avoid having a single bug bringing down your live and backup data. Christian -- Christian Balzer Network/Systems Engineer chibi@xxxxxxx Global OnLine Japan/Rakuten Communications http://www.gol.com/ _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com