Hi, I have built lustre many times and have never ran into this issue before. Can anyone tell me what is happening here, actually how to fix it. CC [M] /usr/src/lustre-1.4.2.1/lustre/ldiskfs/ialloc.o /usr/src/lustre-1.4.2.1/lustre/ldiskfs/ialloc.c: In function `ldiskfs_new_inode'': /usr/src/lustre-1.4.2.1/lustre/ldiskfs/ialloc.c:614: error: `LDISKFS_EXTENTS_FL'' undeclared (first use in this function) /usr/src/lustre-1.4.2.1/lustre/ldiskfs/ialloc.c:614: error: (Each undeclared identifier is reported only once /usr/src/lustre-1.4.2.1/lustre/ldiskfs/ialloc.c:614: error: for each function it appears in.) make[5]: *** [/usr/src/lustre-1.4.2.1/lustre/ldiskfs/ialloc.o] Error 1 Thanks, Jon