Dear Ceph folks, I would like to listen to your advice on the following topic: We have a 6-node Ceph cluster (for RGW usage only ) running on Luminous 12.2.12, and now will add 10 new nodes. Our plan is to phase out the old 6 nodes, and run RGW Ceph cluster with the new 10 nodes on Nautilus version。 I can think of two ways to achieve the above goal. The first method would be: 1) Upgrade the current 6-node cluster from Luminous 12.2.12 to Nautilus 14.2.22; 2) Expand the cluster with the 10 new nodes, and then re-balance; 3) After rebalance completes, remove the 6 old nodes from the cluster The second method would get rid of the procedure to upgrade the old 6-node from Luminous to Nautilus, because those 6 nodes will be phased out anyway, but then we have to deal with a hybrid cluster with 6-node on Luminous 12.2.12, and 10-node on Nautilus, and after re-balancing, we can remove the 6 old nodes from the cluster. Any suggestions, advice, or best practice would be highly appreciated. best regards, Samuel huxiaoyu@horebdata.cn