RHEL 7 or CentOS 7: How to view file extent information for XFS filesystem ?

In ext2, ext3, or ext4 filesystems, we used the command filefrag.

However for xfs filesystem, the filefrag command shows the offset values and the exact file extent values are not visible.

To see the exact file extent information, we need to use the “xfs_bmap” command.

Lets see the mapping of a file called “ifup”.

[root@ngelinux network-scripts]# xfs_bmap -v ifup
ifup:
 EXT: FILE-OFFSET      BLOCK-RANGE      AG AG-OFFSET          TOTAL
   0: [0..15]:         1260240..1260255  0 (1260240..1260255)    16

Similarly we can see the extent information of any other file, say testfile.

[root@ngelinux ~]# xfs_bmap testfile 
testfile:
	0: [0..7]: 6745576..6745583

[root@ngelinux ~]# xfs_bmap -v testfile 
testfile:
 EXT: FILE-OFFSET      BLOCK-RANGE      AG AG-OFFSET        TOTAL
   0: [0..7]:          6745576..6745583  2 (249320..249327)     8
[root@ngelinux ~]# 

Tags: 7bmapcentosextentfilelinuxrhelsystemunixxfs_bmapzfs