Hi, We have been running Ceph in production for a few months and looking at our first big expansion. We are going to be adding 8 new OSDs across 3 hosts to our current cluster of 13 OSD across 5 hosts. We obviously want to minimize the amount of disruption this is going to cause but we are unsure about the impact on the crush map as we add each OSD.
>From the docs I can see that an OSD is added as 'in' and 'down' and wont get objects until the OSD service has started. But what happens to the crushmap while the OSD is 'down', is it recalculated? are objects misplaced and moved on the existing cluster? We think we would like to limit the rebuild of the crush map, is this possible or beneficial. Thanks, Ed Rowley _______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
