I know that your question is regarding the service servers, but may I ask, why you are planning to place so many OSDs ( 300) on so few OSD hosts( 6) (= 50 OSDs per node)? This is possible to do, but sounds like the nodes were designed for scale-up rather than a scale-out architecture like ceph. Going with such "fat nodes" is doable, but will significantly limit performance, reliability and availability, compared to distributing the same OSDs on more thinner nodes. Best regards, Simon Kepp Founder/CEO Kepp Technologies On Fri, Nov 17, 2023 at 10:59 AM Albert Shih <Albert.Shih@xxxxxxxx> wrote: > Hi everyone, > > In the purpose to deploy a medium size of ceph cluster (300 OSD) we have 6 > bare-metal server for the OSD, and 5 bare-metal server for the service > (MDS, Mon, etc.) > > Those 5 bare-metal server have each 48 cores and 256 Gb. > > What would be the smartest way to use those 5 server, I see two way : > > first : > > Server 1 : MDS,MON, grafana, prometheus, webui > Server 2: MON > Server 3: MON > Server 4 : MDS > Server 5 : MDS > > so 3 MDS, 3 MON. and we can loose 2 servers. > > Second > > KVM on each server > Server 1 : 3 VM : One for grafana & CIe, and 1 MDS, 2 MON > other server : 1 MDS, 1 MON > > in total : 5 MDS, 5 MON and we can loose 4 servers. > > So on paper it's seem the second are smarter, but it's also more complex, > so my question are «is it worth the complexity to have 5 MDS/MON for 300 > OSD». > > Important : The main goal of this ceph cluster are not to get the maximum > I/O speed, I would not say the speed is not a factor, but it's not the main > point. > > Regards. > > > -- > Albert SHIH 🦫 🐸 > Observatoire de Paris > France > Heure locale/Local time: > ven. 17 nov. 2023 10:49:27 CET > _______________________________________________ > ceph-users mailing list -- ceph-users@xxxxxxx > To unsubscribe send an email to ceph-users-leave@xxxxxxx > _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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