Re: Proper way of removing osds

Burkhard Linke <Burkhard.Linke@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> · Thu, 21 Dec 2017 11:36:11 +0100



    Hi,

    
    On 12/21/2017 11:03 AM, Karun Josy
      wrote:

    
      Hi,
        

        This is how I remove an OSD from cluster
        

            Take it out

              ceph osd out osdid

              
              Wait for the balancing to finish 

              
            Mark it down

              ceph osd down osdid

              
              Then Purge it

               ceph osd purge osdid --yes-i-really-mean-it

            
        While purging I can see there
              is another rebalancing occurring.
        Is this the correct way to
              removes OSDs, or am I doing something wrong ?
      
    
    The
        procedure is correct, but not optimal.

        
        The first rebalancing is due to the osd being down; the second
        rebalancing is due to fact that removing the osd changes the
        crush weight of the host and thus the base of the overall data
        distribution.

        
        If you want to skip this, you can set the crush weight of the
        to-be-removed osd to 0.0, wait for the rebalancing to be
        finished, and stop and remove the osds afterwards. You can also
        use smaller steps to reduce the backfill impact if necessary,

        
        Regards,

        Burkhard
  

_______________________________________________
ceph-users mailing list
ceph-users@xxxxxxxxxxxxxx
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com