direct use of NVMe and NVRAM storage on the client nodes while keeping the files part of the global filesystem namespace, and OST Overstriping which allows files to store multiple stripes on a single OST to better utilize fast OSS hardware. As well, the LNet Multi-Rail Network Health functionality was improved to work with LNet RDMA router nodes. The PFL functionality was enhanced with Self-Extending Layouts (SEL) to allow file components to be dynamically sized, to better deal with flash OSTs that may be much smaller than disk OSTs within the same filesystem. The release also included a number of smaller improvements, such as balancing DNE remote directory creation across MDTs, using Lazy-size-on-MDT to reduce the overhead of "lfs find", directories with 10M files per shard for ldiskfs, and bulk RPC sizes up to 64MB. Lustre 2.14 was released on February 19, 2021 and includes three main features. Client Data Encryption implements fscrypt to allow file data to be encrypted on the client before network transfer and persistent storage on the OST and MDT. OST Pool Quotas extends the quota framework to allow the assignment and enforcement of quotas on the basis of OST storage pools. DNE Auto Restriping can now adjust how many MDTs a large directory is striped over based on size thresholds defined by the administrator, similar to Progressive File Layouts for directories. Lustre 2.15 was released on June 16, 2022 and includes three main features. Client Directory Encryption expands on the fscrypt data encryption in the 2.14 release to also allow file and directory names to be encrypted on the client before network transfer and persistent storage on the MDT. DNE MDT space balancing automatically balances new directory creation across MDTs in the filesystem in round-robin and/or based on available inodes and space, which in turn helps distribute client metadata workload over MDTs more evenly. For applications using the NVIDIA GPU Direct Storage interface (GDS), the Lustre client can do zero-copy RDMA read and write from the storage server directly into the GPU memory to avoid an extra data copy from CPU memory and extra processing overhead. User Defined Selection Policy (UDSP) allows setting interface selection policies for nodes with multiple network interfaces. Architecture A Lustre file system has three major functional units: One or more metadata servers (MDS) nodes that have one or more metadata target (MDT) devices per Lustre filesystem that stores namespace metadata,