Tune2fs

tune2fs used to show or modify file system parameters on ext4 filesystems

To modify ext4 for metadata checksums tune2fs -O metadata_csum

To disable ext4 metadata checksum: tune2fs -O ^metadata_csum

Show file system characteristics, use -l to show contents of superblock

# tune2fs -l /path/to/device 
# tune2fs -l /dev/sda25
# tune2fs -l /dev/[[cciss]]/c1d1p1
# tune2fs -l /dev/VG_NAME/LV_NAME
# tune2fs -l /dev/mapper/dm-path-name

Change reservation percentage

tune2fs -l /path/to/device | egrep "Reserved block count|Block size"
tune2fs -m 0 /path/to/device

Filesystem state:         clean
Filesystem state:         clean with errors
FS Error count:           61

First error time:         Wed Dec 11 15:40:41 2019
First error function:     htree_dirblock_to_tree
First error line #:       994
First error inode #:      2
First error block #:      0
Last error time:          Sun Dec 15 12:36:44 2019
Last error function:      ext4_find_entry
Last error line #:        1465
Last error inode #:       2
Last error block #:       0

See also

• file, File system, directory, touch, mkdir, ls, ln truncate, fallocate, split, stat, inode, File descriptor, superblock, block size (blockdev), fuser, lsof, scrub, chattr, ulimit (nofiles), cp, mv, file (command), mkfifo, chmod
• File systems: clustered file system, tune2fs mkfs.ext4,superblock, e2fsck, resize2fs, mount, df, umount, UUID, fstab

https://linux.die.net/man/8/tune2fs