Dear Ceph developers, I originally posted this question on the users mailing list and got the suggestion to post it also here. Yesterday I updated my Cephadm-managed cluster from 18.2.2 to 18.2.4, and since then I get a MDS_CLIENTS_BROKEN_ROOTSQUASH error which I didn't get with 18.2.2. As far as I could go with web search, I understood that this error is due to a missing feature in the CephFS client, but also that the feature is going to be introduced with version 19. So I'd need to understand why this error comes out and if it's possible how to fix it. One thing that might be relevant is that some clients trigger the error while some other doesn't: - Ceph 18.2.2 kernel client on Rocky Linux 8: error - Ceph 18.2.4 kernel client on Rocky Linux 9: error - Ceph 18.2.4 kernel client on Archlinux (on kernel 6.10.6): no error From the above facts I'd say that the error might be triggered by some compilation flags, since there's no correlation with client version, is it plausible? Thanks, Nicola