Hello, > Just a note: > With 7+5 you will need 13 host for access your data in case one goes down. As far as I know, EC 7+5 imply ‘erasure size 12 min_size 8’. So I need at least 8 servers access to my data, k=7, m=5, size = k+m = 12 min_size = k+1 = 8 Am I wrong? > Expected in the nexts version allow access data with the EC numbers. I think it is still possible to set min_size = k in Nautilus but it is not recommended. Best, Yoann > -----Mensaje original----- > De: Yoann Moulin <yoann.moulin@xxxxxxx> > Enviado el: martes, 3 de septiembre de 2019 11:28 > Para: ceph-users@xxxxxxx > Asunto: Best osd scenario + ansible config? > > Hello, > > I am deploying a new Nautilus cluster and I would like to know what would be > the best OSD's scenario config in this case : > > 10x 6TB Disk OSDs (data) > 2x 480G SSD previously used for journal and can be used for WAL and/or DB > > Is it better to put all WAL on one SSD and all DBs on the other one? Or put > WAL and DB of the first 5 OSDs on the first SSD and the 5 others on the > second one. > > A more general question, what is the impact on an OSD if we lose the WAL? > The DB? Both? > > I plan to use EC 7+5 on 12 servers and I am OK if I lose one server > temporarily. I have spare servers and I can easily add another one in this > cluster. > > To deploy this cluster, I use ceph-ansible (stable-4.0). I am not sure how > to configure the playbook to use SSD and disks with LVM. > > https://github.com/ceph/ceph-ansible/blob/master/docs/source/osds/scenarios. > rst > > Is this good? > > osd_objectstore: bluestore > lvm_volumes: > - data: data-lv1 > data_vg: data-vg1 > db: db-lv1 > db_vg: db-vg1 > wal: wal-lv1 > wal_vg: wal-vg1 > - data: data-lv2 > data_vg: data-vg2 > db: db-lv2 > db_vg: db-vg2 > wal: wal-lv2 > wal_vg: wal-vg2 > > > Is it possible to let the playbook configure LVM for each disk in a mixed > case? It looks like I must configure LVM before running the playbook but I > am not sure if I missed something. > > Is wal_vg and db_vg can be identical (on VG per SSD shared with multiple > OSDs)? > > Thanks for your help. > > Best regards, > > -- > Yoann Moulin > EPFL IC-IT > _______________________________________________ > ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email > to ceph-users-leave@xxxxxxx > -- Yoann Moulin EPFL IC-IT _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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