Answer is simple.. make use of the below command .
dumpe2fs – dump ext2/ext3/ext4 filesystem information
dumpe2fs prints the super block and blocks group information for the filesystem present on device.
For ex: Suppose :
/dev/sda10 on / type ext4 (rw,relatime,seclabel,data=ordered) dumpe2fs gives below information..
[root@humbles-lap ]# dumpe2fs /dev/sda10 dumpe2fs 1.42.7 (21-Jan-2013) Filesystem volume name: / Last mounted on: / Filesystem UUID: 6da5e19a-e9e8-4ad0-a04f-aeaca04035a2 Filesystem magic number: 0xEF53 Filesystem revision #: 1 (dynamic) Filesystem features: has_journal ext_attr resize_inode dir_index filetype needs_recovery extent flex_bg sparse_super large_file huge_file uninit_bg dir_nlink extra_isize Filesystem flags: signed_directory_hash Default mount options: user_xattr acl Filesystem state: clean Errors behavior: Continue Filesystem OS type: Linux Inode count: 3203072 Block count: 12800000 Reserved block count: 640000 Free blocks: 7857714 Free inodes: 2829010 First block: 0 Block size: 4096 Fragment size: 4096 Reserved GDT blocks: 1020 Blocks per group: 32768 Fragments per group: 32768 Inodes per group: 8192 Inode blocks per group: 512 Flex block group size: 16 Filesystem created: Fri Mar 1 13:39:59 2013 Last mount time: Mon Feb 3 00:34:29 2014 Last write time: Mon Feb 3 00:34:28 2014 Mount count: 71 Maximum mount count: -1 Last checked: Fri Mar 1 13:39:59 2013 Check interval: 0 (<none>) Lifetime writes: 23 GB Reserved blocks uid: 0 (user root) Reserved blocks gid: 0 (group root) First inode: 11 Inode size: 256 Required extra isize: 28 Desired extra isize: 28 Journal inode: 8 First orphan inode: 395012 Default directory hash: half_md4 Directory Hash Seed: cd01fa16-ab8d-422e-9701-33ea367c3df2 Journal backup: inode blocks Journal features: journal_incompat_revoke Journal size: 128M Journal length: 32768 Journal sequence: 0x001c06a6 Journal start: 31366 Group 0: (Blocks 0-32767) [ITABLE_ZEROED] Checksum 0xa877, unused inodes 8123 Primary superblock at 0, Group descriptors at 1-4 Reserved GDT blocks at 5-1024 Block bitmap at 1025 (+1025), Inode bitmap at 1041 (+1041) Inode table at 1057-1568 (+1057) 1076 free blocks, 8123 free inodes, 39 directories, 8123 unused inodes Free blocks: 24012-24575, 32256-32767 Free inodes: 70-8192 Group 1: (Blocks 32768-65535) [INODE_UNINIT, ITABLE_ZEROED] ****************************** If you pass "-h" option it will display only SUPERBLOCK information.