Hi, We have a 3-site Ceph cluster and would like to create a 4+2 EC pool with 2 chunks per datacenter, to maximise the resilience in case of 1 datacenter being down. I have not found a way to create an EC profile with this 2-level allocation strategy. I created an EC profile with a failure domain = datacenter but it doesn't work as, I guess, it would like to ensure it has always 5 OSDs up (to ensure that the pools remains R/W) where with a failure domain = datacenter, the guarantee is only 4. My idea was to create a 2-step allocation and a failure domain=host to achieve our desired configuration, with something like the following in the crushmap rule: step choose indep 3 datacenter step chooseleaf indep x host step emit Is it the right approach? If yes, what should be 'x'? Would 0 work? From what I have seen, there is no way to create such a rule with the 'ceph osd crush' commands: I have to download the current CRUSHMAP, edit it and upload the modified version. Am I right? Thanks in advance for your help or suggestions. Best regards, Michel