SNIA Developer Conference September 15-17, 2025 | Santa Clara, CA
Scaling Secure File Access - what's New in Linux SMB3.1.1: Performance, Security, and Beyond
Lafayette
Wed Sep 17 | 9:30am
Abstract
Accessing servers from Linux over SMB3.1.1 continues to improve in exciting ways. This talk will explore the latest enhancements to the Linux SMB3.1.1 client, enabling more secure, efficient, and compatible access to remote storage across a wide range of SMB3 file servers—including Samba, Azure (the "largest server in the world"), ksmbd, Windows, NetApp, and macOS. There are also exciting improvements to smbdirect (SMB over RDMA), including making this high-performance path easier to use for both the client and server, as well as userspace applications like Samba.
Over the past year, major improvements have been made to performance (e.g. smarter use of directory leases, better metadata caching, and multiple netfs enhancements for improved data caching), security (e.g., new authentication mechanisms and better support for password rotation), and POSIX compatibility (including continued testing and improvement of the SMB3.1.1 POSIX Extensions). Support for special file types has been enhanced, and support for several new Linux system calls has been added. The Linux SMB3.1.1 client remains one of the most active filesystems in the kernel, and userspace tooling has also seen significant evolution. This presentation will also highlight recent progress in the in-kernel SMB server (ksmbd), which is rapidly gaining functionality and performance improvements, making it more useful in embedded, testing, and lightweight server scenarios. Attendees will leave with a practical understanding of how to leverage these new features in real workloads—and a preview of what’s coming next for SMB3.1.1 on Linux.
Learning Objectives
Learn how recent enhancements —such as improved directory caching, metadata handling, and netfs integration—can improve remote file access efficiency for Linux workloads Understand the latest performance, security, and Linux compatibility enhancements in the Linux SMB3.1.1 client Gain insights into recent developments in SMB over RDMA (smbdirect) in Linux and its unified support across client, server (ksmbd.ko), and userspace Explore the recent improvements to the in-kernel SMB server (ksmbd) and how it fits into lightweight and embedded Linux storage scenarios
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