On Wed, Jun 24, 2015 at 4:29 PM, Yueliang <yueliang9527@xxxxxxxxx> wrote: > When I use K+M hosts in the EC pool, if M hosts get down, still have K hosts > active, Can I continue write data to the pool ? If your CRUSH map specifies a failure-domain at the host level (so no two chunks share the same host) then you will be unable to write to the pool. If instead the failure-domain is OSD then with enough OSDs pool writes would still be accepted. > Since there only have K > hosts, not K+M hosts, When client write a data to EC pool , Primary OSD will > split the data to K data pieces,but how about the M coding pieces? is it > still be calculated and where it should be hold ? Same as above, with failure-domain = host then there would be nowhere to put the M coding pieces. _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com