Abstract:
The open source file and print service software Samba 4.25 was officially released recently, becoming the latest stable version of the project that provides file and print sharing services for Linux servers and Windows systems. The most noteworthy change in this update is the first addition of experimental support for SMB3 Persistent Handles, also known as SMB3 persistent handles. It also introduces the new Ceph RGW virtual file system module and improves audit logs, domain encryption and other functions.
SMB3 persistent handle is one of the core features of this update of Samba 4.25. Its main goal is to provide a foundation for more transparent failover capabilities in the future. In traditional SMB connections, if the server restarts, fails, or is briefly interrupted, the client usually needs to re-establish the connection, and the originally opened file handle may have expired, and the application may also be affected.
After enabling SMB3 persistent handles, the client can reconnect to the server after a server restart or interruption and continue to use the file handle it has obtained before and is still valid. In other words, even if the server is temporarily offline, the client still has the opportunity to continue accessing the original file after the connection is reestablished, thereby reducing the interruption of file access caused by server failure.
However, this feature is still experimental support and comes at a significant performance cost. Samba developers pointed out that SMB3 persistent handles will generate additional storage overhead for each open, update, lease, and close operation, requiring double storage processing, and therefore may cause "significant" performance losses.
Therefore, Samba 4.25 does not simply recommend that all users enable this feature immediately, but as an experimental infrastructure for high availability and transparent failover scenarios. For ordinary file servers, users still need to weigh the relationship between continuous availability and performance overhead based on actual needs.
In addition to SMB3 persistent handles, Samba 4.25 also adds the new Ceph RGW VFS module. Through this module, the Ceph Object Gateway, which is the storage bucket in the Ceph Object Gateway, can provide access through SMB shares, thereby further connecting object storage with traditional file sharing environments.
This change is particularly meaningful for users who are already using Ceph to build large-scale storage infrastructure. In the past, object storage and SMB file sharing usually belonged to different access systems, but the new VFS module allows the object storage resources in Ceph RGW to be provided to clients that support the SMB protocol through Samba, thereby expanding the scope of application of Ceph object storage in traditional Windows/Linux file sharing environments.
Samba 4.25 also improves the audit log in JSON format. For enterprise environments that need to record and analyze file access, user operations, and server activities, more complete JSON audit logs can be more easily processed by log analysis systems, security platforms, and other automated tools.
At the same time, Samba 4.25 adjusts the default settings for domain encryption type and sets AES as the default encryption method. This move further promotes Samba's use of more modern encryption mechanisms while reducing the system's continued reliance on older encryption types in its default configuration.
Samba itself is a very important open source infrastructure project that enables Linux and other Unix-like systems to interoperate with Windows environments for file and print services by implementing the SMB/CIFS protocol used by Microsoft Windows. A large number of enterprise file servers, NAS devices, and Linux servers rely on Samba to provide Windows-compatible network file sharing capabilities.
As enterprise infrastructure increasingly emphasizes high availability, it becomes more important to avoid interruption of user work as much as possible when a server fails or restarts. It is in this context that SMB3 persistent handles were added to Samba 4.25. Although still in the experimental stage, it lays the foundation for more complete transparent failover in the future.
It is worth noting that this update of Samba 4.25 is not a version upgrade that simply adds new features, but improves many aspects such as file service continuity, object storage integration, security auditing and encryption mechanisms. In particular, SMB3 persistent handles and Ceph RGW support strengthen Samba's application potential in high-availability file services and modern distributed storage environments respectively.
Samba 4.25 is now released as the latest stable version, and the source code and complete 4.25 version update instructions have been provided simultaneously. For users running Samba servers, if they want better compatibility, new storage backend capabilities, and the latest fixes, they can consider upgrading to this version; while experimental features such as SMB3 persistent handles are more suitable for testing and evaluation before being put into production environments based on specific business needs.
Learn more:
https://www.samba.org/samba/history/samba-4.25.0.html
Comments