Assuming size=3 and min_size=2 It will run degraded (read/write capable) until a third host becomes available at which point it will backfill the third copy on the third host. It will be unable to create the third copy of data if no third host exists. If an additional host is lost the data will become inactive+degraded (below min_size) and will be unavailable for use. Though data will not be lost assuming no further failures beyond the 2 full hosts occurs and again if the second and third host comes back the data will recover. Always best to have an additional host beyond the size setting for this reason. Respectfully, *Wes Dillingham* wes@xxxxxxxxxxxxxxxxx LinkedIn <http://www.linkedin.com/in/wesleydillingham> On Mon, May 1, 2023 at 11:34 AM wodel youchi <wodel.youchi@xxxxxxxxx> wrote: > Hi, > > When creating a ceph cluster, a failover domain is created, and by default > it uses host as a minimal domain, that domain can be modified to chassis, > or rack, ...etc. > > My question is : > Suppose I have three osd nodes, my replication is 3 and my failover domain > is host, which means that each copy of data is stored on a different node. > > What happens when one node crashes, does Ceph use the remaining free space > on the other two to create the third copy, or the ceph cluster will run in > degraded mode, like a RAID5 > which lost a disk. > > Regards. > _______________________________________________ > 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
 |