Hi, for production (with enough OSDs) is three replicas the right choice. The chance for data loss if two ODSs fails at one time is to high. And if this happens most of your data ist lost, because the data is spead over many OSDs... And yes - two replicas is faster for writes. Udo On 02.11.2015 11:10, Wah Peng wrote: > Hello, > > for production application (for example, openstack's block storage), > is it better to setup data to be stored with two replicas, or three > replicas? is two replicas with better performance and lower cost? > > Thanks. > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com