The release of Stratis 3.3 has been published, developed by Red Hat and the Fedora community to unify and simplify the tools for configuring and managing a pool of one or more local storage devices. Stratis provides features such as dynamic storage allocation, snapshots, integrity checks, and layer creation for caching. Stratis support is integrated into Fedora and RHEL distributions starting from Fedora 28 and RHEL 8.2 releases. The project code is distributed under the MPL 2.0 license.
The system largely mirrors the capabilities of advanced partition management tools like ZFS and Btrfs, but is implemented as a layer (the stratisd daemon) operating above the Linux kernel's device-mapper subsystem (utilizing modules dm-thin, dm-cache, dm-thinpool, dm-raid, and dm-integrity) and the XFS filesystem. Unlike ZFS and Btrfs, Stratis components operate solely in user space and do not require specific kernel module loading. The project is initially presented as not requiring expert qualifications for storage system administration.
Management is provided through a D-Bus API and a cli utility. Stratis has been tested with block devices based on LUKS (encrypted partitions), mdraid, dm-multipath, iSCSI, LVM logical volumes, as well as various HDDs, SSDs, and NVMe drives. When there is one disk in the pool, Stratis allows the use of logical partitions with snapshot support for reverting changes. When multiple drives are added to the pool, it becomes possible to logically combine drives into a contiguous area. Features such as RAID, data compression, deduplication, and fault tolerance are not yet supported but are planned for the future.
In the new version:
- Support has been added for expanding the size of physical devices, allowing additional disk space to be added to the Stratis pool that has become available on the storage device (for example, when expanding a RAID array).
- The command ‘stratis pool extend-data’ has been added to allocate additional disk space that has become available on one of the devices to a specific storage pool. To track size changes of devices, a special alert has been added to the output of the ‘stratis pool list’ command, and the ‘stratis blockdev list’ command now includes information on the size differences between the pool and the device.
- The allocation of space for metadata related to storage devices and dynamic space allocation (‘thin provisioning’) has been improved. This change has reduced fragmentation in metadata storage.
- The verification of executable files in the Clevis framework, used for automatic encryption and decryption of data in disk partitions, has been reworked. The verification is now performed every time a user command requires access to Clevis (previously, it was only checked once at the launch of Stratis), which resolves issues with using Clevis that was installed after starting stratisd.
Source: opennet.ru
