Voldfstab

Voldfstab is a configuration file used by the Android Volume Daemon (vold) to define how storage volumes are mounted and managed by the system. It describes static information about external storage devices and their intended mount points, such as SD cards, USB storage, and emulated storage. The file is typically located at /system/etc/vold.fstab, though its exact path can vary by device or ROM.

In Voldfstab, each non-comment line defines a volume and provides fields that specify the device path (the block device or device node), the mount point where the volume should be mounted in the file system, the filesystem type, and any mount options. A common directive used in older Android versions is dev_mount, which maps a device path to a mount point. Other formats in different Android releases use similar entries to declare volume IDs, labels, and related metadata. Vold and voldfstab work together with system events to mount or unmount volumes as hardware changes, such as insertion or removal of cards or USB storage.

Modifying voldfstab is typically restricted to rooted devices or custom ROMs and can affect how storage is presented to users and apps. Changes may require a reboot or remounting to take effect. Over time, storage management on Android has evolved with newer mechanisms like StorageManager and FUSE-based emulation, reducing reliance on voldfstab in newer releases, but it remains part of the historical and some current implementations for legacy mount configurations.

See also: Android volume management, vold, storage management, emulated storage.