I have a Ceph instance I'm wherein I'm trying to use erasure coding with RBD (and libvirt). I've followed https://docs.ceph.com/en/latest/rados/operations/erasure-code/#erasure-codin... and enabled overwrites so that RBD can be used. In doing so, I've set the data_pool to the erasure coded pool, with set to the replicated pool. I have the following in ceph.conf: rbd_default_data_pool = libvirt-pool-ec Here's an rbd info on the image I've created (notice the "data_pool" config): rbd image 'xxxxxxx': size 500 GiB in 128000 objects order 22 (4 MiB objects) snapshot_count: 0 id: 7e37e442592b data_pool: libvirt-pool-ec block_name_prefix: rbd_data.6.7e37e442592b format: 2 features: layering, exclusive-lock, object-map, fast-diff, deep-flatten, data-pool op_features: flags: create_timestamp: Fri Sep 13 16:34:06 2024 access_timestamp: Fri Sep 13 16:34:06 2024 modify_timestamp: Fri Sep 13 16:34:06 2024 The problem, when I attach this rbd image to a VM, I cannot write to it at all, I get an I/O error. But, when I create and rbd image without the "rbd_default_data_pool = libvirt-pool-ec" setting, I can write fine. Wanted to see if anyone has any ideas, maybe I'm missing something simple. Thanks in advance!