On Mon, Aug 20, 2018 at 06:13:26AM -0400, David Turner wrote: :There is a thread from the ceph-large users ML that covered a way to do :this change without shifting data for an HDD only cluster. Hopefully it :will be helpful for you. : : :httpists.ceph.com/pipermail/ceph-large-ceph.com/2018-April/000106.html Wish I knew that list existed before I thrashed my entire cloud for a week doing exactly this. 95% data move on a cluster that already experiencing IO exhaustion was not fun. Luckily it was "only" 0.5PB -Jon :On Mon, Aug 20, 2018, 5:42 AM Enrico Kern <enrico.kern@xxxxxxxxxx> wrote: : :> Hmm then is not really an option for me. Maybe someone from the devs can :> shed a light why it is doing migration as long you only have OSDs with the :> same class? I have a few Petabyte of Storage in each cluster. When it :> starts migrating everything again that will result in a super big :> performance bottleneck. My plan was to set the existing pools to use the :> new crush rule hdd only and add ssd osds later. :> :> On Mon, Aug 20, 2018 at 11:22 AM Marc Roos <M.Roos@xxxxxxxxxxxxxxxxx> :> wrote: :> :>> :>> I just recently did the same. Take into account that everything starts :>> migrating. How weird it maybe, I had hdd test cluster only and changed :>> the crush rule to having hdd. Took a few days, totally unnecessary as :>> far as I am concerned. :>> :>> :>> :>> :>> -----Original Message----- :>> From: Enrico Kern [mailto:enrico.kern@xxxxxxxxxx] :>> Sent: maandag 20 augustus 2018 11:18 :>> To: ceph-users@xxxxxxxxxxxxxx :>> Subject: Set existing pools to use hdd device class only :>> :>> Hello, :>> :>> right now we have multiple HDD only clusters with ether filestore :>> journals on SSDs or on newer installations WAL etc. on SSD. :>> :>> I plan to extend our ceph clusters with SSDs to provide ssd only pools. :>> In luminous we have devices classes so that i should be able todo this :>> without editing around crush map. :>> :>> In the device class doc it says i can create "new" pools to use only :>> ssds as example: :>> :>> ceph osd crush rule create-replicated fast default host ssd :>> :>> what happens if i fire this on an existing pool but with hdd device :>> class? I wasnt able to test thi yet in our staging cluster and wanted to :>> ask whats the way todo this. :>> :>> I want to set an existing pool called volumes to only use osds with hdd :>> class. Right now all OSDs have hdds. So in theory it should not use :>> newly created SSD osds once i set them all up for hdd classes right? :>> :>> So for existing pool running: :>> :>> ceph osd crush rule create-replicated volume-hdd-only volumes default :>> hdd ceph osd pool set volumes crush_rule volume-hdd-only :>> :>> :>> should be the way to go right? :>> :>> :>> Regards, :>> :>> Enrico :>> :>> -- :>> :>> :>> Enrico Kern :>> :>> VP IT Operations :>> :>> :>> enrico.kern@xxxxxxxxxx :>> +49 (0) 30 555713017 / +49 (0) 152 26814501 :>> :>> skype: flyersa :>> LinkedIn Profile <https://www.linkedin.com/in/enricokern> :>> :>> :>> <http://goog_59398030/> <https://www.glispa.com/> :>> :>> :>> Glispa GmbH | Berlin Office :>> :>> Stromstr. 11-17 <https://goo.gl/maps/6mwNA77gXLP2> :>> Berlin, Germany, 10551 <https://goo.gl/maps/6mwNA77gXLP2> :>> :>> Managing Director Din Karol-Gavish :>> Registered in Berlin :>> AG Charlottenburg | :>> < :>> https://maps.google.com/?q=Sonnenburger+Stra%C3%9Fe+73+10437+Berlin%C2%A0%7C+%3Chttps://maps.google.com/?q%3DSonnenburgerstra%25C3%259Fe%2B73%2B10437%2BBerlin%25C2%25A0%257C%25C2%25A0Germany%26entry%3Dgmail%26source%3Dg%3E%C2%A0Germany&entry=gmail&source=g> :>> :>> HRB 114678B ––––––––––––––––––––––––––––– :>> :>> :>> :> :> -- :> :> *Enrico Kern* :> VP IT Operations :> :> enrico.kern@xxxxxxxxxx :> +49 (0) 30 555713017 / +49 (0) 152 26814501 :> skype: flyersa :> LinkedIn Profile <https://www.linkedin.com/in/enricokern> :> :> :> <http://goog_59398030/> <https://www.glispa.com/> :> :> *Glispa GmbH* | Berlin Office :> Stromstr. 11-17 <https://goo.gl/maps/6mwNA77gXLP2> :> Berlin, Germany, 10551 <https://goo.gl/maps/6mwNA77gXLP2> :> :> Managing Director Din Karol-Gavish :> Registered in Berlin :> AG Charlottenburg | :> <https://maps.google.com/?q=Sonnenburger+Stra%C3%9Fe+73+10437+Berlin%C2%A0%7C+%3Chttps://maps.google.com/?q%3DSonnenburgerstra%25C3%259Fe%2B73%2B10437%2BBerlin%25C2%25A0%257C%25C2%25A0Germany%26entry%3Dgmail%26source%3Dg%3E%C2%A0Germany&entry=gmail&source=g> HRB :> 114678B :> ––––––––––––––––––––––––––––– :> _______________________________________________ :> 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 -- _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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