Filesystem Tasks: Formatting, Integrity & Repair 💽¶

Every partition needs a filesystem structure to store files, directories, and permissions. This guide explains how to format drives, choose the right filesystem, run health checks (fsck), repair corruption, and mount filesystems in fparted.

1. Choosing the Right Filesystem¶

Not sure which filesystem to pick? Here is a practical comparison based on real-world use cases:

Filesystem	Best Used For	Pros	Considerations
ext4	Linux rootfs, Termux chroots, internal storage, backups	Standard Linux filesystem; rock-solid journaling, POSIX permissions, fast recovery	Windows and macOS cannot read ext4 without third-party drivers.
exFAT	MicroSD cards, USB OTG flash drives, camera storage	Cross-platform (Android, Windows, macOS, Linux); supports files $>4\text{ GB}$	No native POSIX permissions or journaling; sensitive to sudden disconnects.
FAT32	Small USB drives ($<32\text{ GB}$), EFI System Partitions (ESP)	Maximum compatibility with every operating system, car stereo, and game console	Maximum single file size is strictly limited to 4 GiB.
F2FS	High-speed internal flash memory, benchmark performance	Specifically engineered for NAND flash pages; fast random I/O write speeds	Shrinking is not supported by filesystem toolchain.
NTFS	Windows external backup hard drives, large video storage	Journaled, supported by modern Windows PCs	Linux/Android write drivers run via FUSE or kernel module.
Btrfs	Advanced storage setups, subvolumes, snapshots	Copy-on-Write (CoW), checksum integrity protection	Requires modern kernel and careful mount parameter management.
Linux Swap	Virtual memory paging space for Android	Lowers RAM pressure on multitasking and Android-x86	Not a data filesystem; invisible in file managers.

2. Formatting a Partition¶

Formatting replaces the existing filesystem structure with a clean, initialized volume.

┌────────────────────────────────────────────────────────────────────────┐
│  Format Partition: /dev/block/mmcblk1p1                                │
│                                                                        │
│  Filesystem: [ ext4 ▼ ]                                                │
│  Volume Label: [ USB_BACKUP       ]  (Max 16 chars for ext4/FAT)       │
│                                                                        │
│  Advanced Options:                                                     │
│  [x] Force 4096-byte block size (Optimized for flash performance)       │
│  [ ] Create LUKS Encrypted container                                   │
│                                                  [ Cancel ]  [ Format ]│
└────────────────────────────────────────────────────────────────────────┘

Step-by-Step¶

Select the partition you want to format in the list or graph.
Tap Format (or press Ctrl + F).
Select your desired filesystem from the dropdown.
Enter an optional Volume Label (e.g., FlashDrive, RootFS).
Tap Format to stage the formatting command into the Operations Queue.

[!WARNING] Formatting permanently erases all existing files and directory structures inside that partition. Ensure you have backed up any critical files before clicking Apply.

3. Checking & Repairing Filesystems (`fsck`)¶

If a USB drive was unplugged without safely ejecting, or your Android device rebooted unexpectedly during heavy writes, the filesystem metadata may be marked as "dirty" or corrupted.

flowchart LR
    A["Select Unmounted Partition"] --> B["Tap Check & Repair"]
    B --> C{"Choose Mode"}
    C -->|"Read-Only Check"| D["Non-destructive inspection (e2fsck -n / fsck.fat -v)"]
    C -->|"Automatic Repair"| E["Fix bad superblocks & orphans (e2fsck -fy / fsck.fat -a)"]

How to Run a Check¶

Ensure the partition is Unmounted (mounted partitions cannot be safely checked).
Tap Check & Repair (or press Ctrl + K).
Select your mode:
Read-Only Check Mode: Inspects directory trees, inode tables, and allocation maps without modifying a single bit on disk. Safe to run anytime.
Automatic Repair Mode: Automatically resolves orphan inodes, updates superblock transaction journals, and restores corrupted allocation clusters (-fy / -a flags).
Tap Run Check. The live terminal output from the underlying utility (e2fsck, fsck.fat, fsck.f2fs, ntfsfix, btrfs check) streams in real-time.

4. Mounting & Unmounting Volumes¶

Mounting attaches a partition's filesystem tree to Android's Virtual File System (VFS) so you can browse its files.

Mounting¶

Select the partition and tap Mount (or press Ctrl + Shift + M).
fparted mounts the filesystem to /mnt/runtime/default/<device_name> or your chosen custom mount point.
You can now access the files through root file managers (such as MiXplorer, Solid Explorer) or Termux.

Unmounting¶

Select the mounted partition.
Tap Unmount (or press Ctrl + Shift + U).
fparted flushes all cached dirty pages to flash memory (sync) and cleanly unlinks the VFS mount point.

[!IMPORTANT] Always unmount your drives before physically unplugging USB cables or swapping SD cards to prevent filesystem corruption!