Hi, it’s not about the OSD RAM recommendations here. This ist the only point that is absolutely clear to us. It’s about the MON and MDS recommendations. The official Ceph documentation also says „1 GB per daemon instance“ for monitors and metadata hosts. But for what daemon instances? There will be 3 monitor and 1 metadata servers for now, each of them running one of their daemon instances. Or am I completely wrong here? So this would lead to 1 GB of RAM per node (disregarding OS needs), which I can’t believe is true. Otherwise there will be 180 OSD instances, which would lead to 180 GB of RAM per monitor and metadata node, which I don’t want to believe is true 😉 Kind regards Sebastian -- Sebastian Wiesner IT-Systemadministrator / Application Developer Department of Operative Processes and Systems (OPS) Dresden University of Technology Center for Information Services and High Performance Computing (ZIH) D-01062 Dresden, Germany phone: +49 351 463-37828 fax: +49 351 463-32164 e-mail: sebastian.wiesner(a)tu-dresden.de WWW: http://www.tu-dresden.de/zih Von: Bogdan Adrian Velica <vbogdan(a)gmail.com> Datum: Mittwoch, 10. Juli 2019 um 09:13 An: "Wiesner, Sebastian" <sebastian.wiesner(a)tu-dresden.de> Cc: "ceph-users(a)ceph.io" <ceph-users(a)ceph.io> Betreff: Re: [Ceph-users] Ceph MON onde RAM recommandations Hi, From what I can remember there is a bit of a difference if you have OSD daemons on SSD or HDD and their capacity... If you have the OSD daemons on HDD the recommendation is to have a bit more than 1G of RAM. If you have OSD on SSD disk then 1G of ram is the minim recommendation ... Best regards, Bogdan. On Tue, Jul 9, 2019 at 7:55 PM Sebastian Wiesner <sebastian.wiesner(a)tu-dresden.de> wrote: Hi community, we’re designing our first Ceph cluster here and we’re struggeling with the MON (and also MDS) nodes RAM recommendations. It sais „like 1GB per daemon instance“, but what daemons are meant here? The range is from per MON (MDS) daemon, which would be fairly low, to per OSD daemon, which would be fairly high. Any help would be appreciated. Kind regards Sebastian -- Sebastian Wiesner IT-Systemadministrator / Application Developer Department of Operative Processes and Systems (OPS) Dresden University of Technology Center for Information Services and High Performance Computing (ZIH) D-01062 Dresden, Germany phone: +49 351 463-37828 fax: +49 351 463-32164 e-mail: sebastian.wiesner(a)tu-dresden.de WWW: http://www.tu-dresden.de/zih _______________________________________________ Ceph-users mailing list -- ceph-users(a)ceph.io To unsubscribe send an email to ceph-users-leave(a)ceph.io