The release of the Stratis 3.3 project, developed by Red Hat and the Fedora community to unify and simplify tools for configuring and managing a pool of one or more local drives, has been published. Stratis provides features such as dynamic storage allocation, snapshots, integrity, and caching layers. Stratis support has been integrated into Fedora and RHEL distributions since the Fedora 28 and RHEL 8.2 releases. The project code is distributed under the MPL 2.0 license.
The system largely repeats the advanced ZFS and Btrfs partition management tools in its capabilities, but is implemented as a layer (stratisd daemon) running on top of the device-mapper subsystem of the Linux kernel (modules dm-thin, dm-cache, dm-thinpool, dm- raid and dm-integrity) and the XFS file system. Unlike ZFS and Btrfs, Stratis components work only in user space and do not require loading specific kernel modules. The project is initially presented as not requiring the qualifications of an expert in storage systems for administration.
D-Bus API and cli-utility are provided for control. Stratis has been tested with LUKS-based block devices (encrypted partitions), mdraid, dm-multipath, iSCSI, LVM logical volumes, and various hard drives, SSDs, and NVMe drives. If there is one disk in the pool, Stratis allows you to use snapshot-enabled logical partitions to roll back changes. When multiple drives are added to a pool, the drives can be logically combined into a contiguous area. Features such as RAID, data compression, deduplication, and failover are not currently supported, but are planned for the future.
In the new version:
- Support has been added for expanding the size of physical devices, allowing you to add additional disk space to the Stratis pool that has become available on the storage device (for example, when expanding a RAID array).
- Added "stratis pool extend-data" command to add additional disk space to a specific storage pool that appeared on one of the devices. Added a special warning to the output of the "stratis pool list" command to monitor device size changes, and added information about differences in pool and device sizes to the "stratis blockdev list" command.
- Improved space allocation for metadata related to storage devices and dynamic storage space allocation ("thin provisioning"). The change allowed to reduce fragmentation when storing metadata.
- The check of executable files of the Clevis framework, used for automatic encryption and decryption of data in disk partitions, has been redesigned. The check is now performed every time a user command needs to call Clevis (previously it was only checked once, when Stratis was started), which solves problems with using Clevis installed after starting stratisd.
Source: opennet.ru