Create an erasure coded rbd pool
ceph osd pool create ec-pool 1024 1024 erasure 8-3
ceph osd pool set data01 allow_ec_overwrites true
rbd pool init ec-pool
note
Many things can be changed later in ceph during the runtime. However, the settings for the distribution of data and coding chunks must be defined when the EC pool is created. This means you should think carefully about what you plan to do with the pool in the future.
Create a erasure coded rbd image, in the EC data pool and for the metadata (OMAP objects) you need the replicated target-pool:
rbd create --size 25G --data-pool ec-pool/origin-image target-pool/new-image
rbd info target-pool/new-image