Read magic signatures from a block device or image.
Section: Inventory and Capacity
Inspect a disk image or device signature
bash
bash
file -s /dev/sdbExplanation
Read magic signatures from a block device or image.
Learn the surrounding workflow
Compare similar commands or jump into common fixes when this command is part of a bigger troubleshooting path.
Related commands
Same sheet · prioritizing Inventory and Capacity
List block devices as a tree
Show disks, partitions, loop devices, and mountpoints.
Show filesystems with UUIDs
Display filesystem type, label, UUID, and mountpoint.
Select custom lsblk columns
Useful when you want clean inventory output for documentation or scripts.
Probe block devices for signatures
Read known filesystem, RAID, and partition metadata.
Show mounted filesystems
Display the live mount tree with source, target, and options.