You need to use a command called dumpe2fs. It displays lots of useful information about your ext2 or ext3 file system. General syntax is as follows:
dumpe2fs /dev/device
It displays following type of information:
- Filesystem volume name
- Last mounted on
- Filesystem features: has_journal ext_attr filetype needs_recovery sparse_super
- Default mount options
- Filesystem state
- Filesystem OS type
- Information about blocks etc
For example, display information about /dev/hdb1
$ dumpe2fs /dev/hdb1
Output:
Filesystem volume name: / Last mounted on: Filesystem UUID: 7a965fb9-bf9e-4ed5-8a01-321386b843d9 Filesystem magic number: 0xEF53 Filesystem revision #: 1 (dynamic) Filesystem features: has_journal ext_attr filetype needs_recovery sparse_super Default mount options: (none) Filesystem state: clean Errors behavior: Continue Filesystem OS type: Linux Inode count: 2443200 Block count: 4883752 Reserved block count: 244187 Free blocks: 677028 Free inodes: 2063116 First block: 0 Block size: 4096 Fragment size: 4096 Blocks per group: 32768 Fragments per group: 32768 Inodes per group: 16288 Inode blocks per group: 509 Last mount time: Thu Mar 16 23:25:43 2006 Last write time: Thu Mar 16 23:25:43 2006 Mount count: 20 Maximum mount count: 30 Last checked: Sun Mar 12 01:16:43 2006 Check interval: 0 () Reserved blocks uid: 0 (user root) Reserved blocks gid: 0 (group root) First inode: 11 Inode size: 128 Journal inode: 8 First orphan inode: 782426 Journal backup: inode blocks Group 0: (Blocks 0-32767) Primary superblock at 0, Group descriptors at 1-2 Block bitmap at 3 (+3), Inode bitmap at 4 (+4) Inode table at 5-513 (+5) 93 free blocks, 15966 free inodes, 8 directories Free blocks: 8844-8855, 9099-9126, 9129-9137, 9139-9142, 9146-9151, 9154-9155, 9158-9165, 9170, 9172, 9174-9176, 9178-9179 , 9182-9189, 9191, 9193, 9196-9197, 9200-9204 Free inodes: 114, 126-164, 172, 362-547, 549-589, 591-16288 Group 1: (Blocks 32768-65535) Backup superblock at 32768, Group descriptors at 32769-32770 Block bitmap at 32771 (+3), Inode bitmap at 32772 (+4) Inode table at 32773-33281 (+5) 6250 free blocks, 13747 free inodes, 143 directories Free blocks: 38912-38919, 56874-57138, 57141-57343, .... ..... .