1tune2fs metadata_csum test 2Creating filesystem with 524288 1k blocks and 65536 inodes 3Superblock backups stored on blocks: 4 8193, 24577, 40961, 57345, 73729, 204801, 221185, 401409 5 6Allocating group tables: done 7Writing inode tables: done 8Creating journal (16384 blocks): done 9mke2fs: Operation not supported for inodes containing extents while creating huge files 10Writing superblocks and filesystem accounting information: done 11 12Pass 1: Checking inodes, blocks, and sizes 13Pass 2: Checking directory structure 14Pass 3: Checking directory connectivity 15Pass 4: Checking reference counts 16Pass 5: Checking group summary information 17 18Exit status is 0 19tune2fs -O metadata_csum test.img 20Extents are not enabled. The file extent tree can be checksummed, whereas block maps cannot. Not enabling extents reduces the coverage of metadata checksumming. Re-run with -O extent to rectify. 2164-bit filesystem support is not enabled. The larger fields afforded by this feature enable full-strength checksumming. Run resize2fs -b to rectify. 22Exit status is 0 23 24Change in FS metadata: 25@@ -2,7 +2,7 @@ 26 Last mounted on: <not available> 27 Filesystem magic number: 0xEF53 28 Filesystem revision #: 1 (dynamic) 29-Filesystem features: has_journal ext_attr resize_inode dir_index filetype sparse_super large_file 30+Filesystem features: has_journal ext_attr resize_inode dir_index filetype sparse_super large_file metadata_csum 31 Default mount options: user_xattr acl 32 Filesystem state: clean 33 Errors behavior: Continue 34@@ -29,6 +29,7 @@ 35 Journal inode: 8 36 Default directory hash: half_md4 37 Journal backup: inode blocks 38+Checksum type: crc32c 39 Journal features: (none) 40 Journal size: 16M 41 Journal length: 16384 42@@ -36,7 +37,7 @@ 43 Journal start: 0 44 45 46-Group 0: (Blocks 1-8192) 47+Group 0: (Blocks 1-8192) [ITABLE_ZEROED] 48 Primary superblock at 1, Group descriptors at 2-3 49 Reserved GDT blocks at 4-259 50 Block bitmap at 260 (+259) 51@@ -45,7 +46,7 @@ 52 0 free blocks, 1013 free inodes, 2 directories 53 Free blocks: 54 Free inodes: 12-1024 55-Group 1: (Blocks 8193-16384) 56+Group 1: (Blocks 8193-16384) [ITABLE_ZEROED] 57 Backup superblock at 8193, Group descriptors at 8194-8195 58 Reserved GDT blocks at 8196-8451 59 Block bitmap at 8452 (+259) 60@@ -54,6 +55,6 @@ 61 0 free blocks, 1024 free inodes, 0 directories 62 Free blocks: 63 Free inodes: 1025-2048 64-Group 2: (Blocks 16385-24576) 65+Group 2: (Blocks 16385-24576) [ITABLE_ZEROED] 66 Block bitmap at 16385 (+0) 67 Inode bitmap at 16386 (+1) 68Pass 1: Checking inodes, blocks, and sizes 69Pass 2: Checking directory structure 70Pass 3: Checking directory connectivity 71Pass 4: Checking reference counts 72Pass 5: Checking group summary information 73 74Exit status is 0 75