mkfs.bcachefs

creates a bcachefs filesystem on one or more devices

TLDR

Create a bcachefs filesystem inside a partition

$ sudo mkfs.bcachefs [/dev/sdXY]

Create a bcachefs filesystem with a volume label

$ sudo mkfs.bcachefs -L [volume_label] [/dev/sdXY]

SYNOPSIS

mkfs.bcachefs [options] devices...

mkfs.bcachefs creates a bcachefs filesystem on one or more devices. Bcachefs is a modern copy-on-write filesystem for Linux with features including checksumming, compression, encryption, snapshots, and multi-device support with tiering.
The filesystem can span multiple devices with configurable replication, allowing for RAID-like redundancy without a separate volume manager. Different storage tiers (fast SSD, slow HDD) can be combined in a single filesystem.
Bcachefs aims to provide the features of ZFS and Btrfs with better performance and simpler administration.

PARAMETERS

-L, --fs_label _label_

Set the filesystem volume label

--replicas _n_

Number of data replicas (for multi-device setups)

--foreground_target _target_

Target for foreground writes

--promote_target _target_

Target for promoting cached data

--metadata_replicas _n_

Number of metadata replicas

--data_checksum _type_

Data checksum algorithm (crc32c, crc64, xxhash, none)

--compression _type_

Compression algorithm (lz4, gzip, zstd, none)

--encrypted

Enable filesystem encryption

CAVEATS

Destroys all data on the target devices. Bcachefs was merged into the Linux kernel in version 6.7 but is still considered experimental. Multi-device configurations require careful planning for data safety. Encryption requires setting up a passphrase during creation.

HISTORY

Bcachefs was developed by Kent Overstreet, evolving from the bcache block caching layer. After years of development, it was merged into the Linux kernel mainline in December 2023.