Thanks all, I'm going to investigate rbd-mirror further. K. On 14-05-2020 09:30, Anthony D'Atri wrote:
It’s entirely possible — and documented — to mirror individual images. Your proposal to use snapshots is reinventing the wheel, but with less efficiency.
https://docs.ceph.com/docs/nautilus/rbd/rbd-mirroring/#image-configuration
ISTR that in Octopus the need for RBD journals is gone, but am not positive.
For done 1-2 volumes at a time you’ll want to increase two tunables to avoid protracted syncing. Without these I’ve experienced a volume of just a few TB take multiple hours to converge, and some that got increasingly behind over time.
rbd_mirror_journal_max_fetch_bytes: section: "client" value: "33554432"
rbd_journal_max_payload_bytes: section: "client" value: "8388608"