Taking the message from Samba to be: > No locks available error. This can happen when using 64 bit lock offsets > on 32 bit NFS mounted file systems. Is Gluster 3.1.4's NFS itself 32-bit or 64-bit? From here: http://europe.gluster.org/community/documentation/index.php/Gluster_3.1:_NFS_Frequently_Asked_Questions#Application_fails_with_.22Invalid_argument.22_or_.22Value_too_large_for_defined_data_type.22_error. it looks like 3.1 is 64-bit NFS. The file systems in the 2 Gluster mounts are ext4 for one and xfs for the other. All the systems are themselves, and have always been, 64-bit. The one that's ext4 I had at some point added "posix locking = no" to smb.conf to avoid a problem that I don't recall clearly, but it wasn't the present one. The Samba docs advise that that setting should never be required, and that it's about coordinating the smb lock table with the posix one. But there are old reports on the Samba mailing list of it curing various things. I've added that for the xfs-based Gluster share now. Hoping someone has a clearer view of this. Are there respects in which Gluster's NFS is 32-bit rather than 64? Or that xfs on a 64-bit system is? Or ext4? I haven't been able to work out just which operation exhausted the locks, but it's more likely to have been on the xfs Gluster nfs mount, as more was going on there at the time things went bad. Whit