# echo KITTENS > file
# lfs getstripe file
file
lmm_stripe_count:   1
lmm_stripe_size:    1048576
lmm_layout_gen:     0
lmm_stripe_offset:  1
                    obdidx               objid           objid           group
                         1                            2            0x2      0x240000401
# lfs fid2path /mnt/lustre '[0x240000401:0x2:0x0]'
ioctl err -5: Input/output error (5)
fid2path error: Input/output error
# stat '.lustre/fid/[0x240000401:0x2:0x0]'

Message from syslogd@m at Feb  5 17:13:30 ...
 kernel:LustreError: 4289:0:(mdt_handler.c:2243:mdt_obj()) ASSERTION( lu_device_is_mdt(o-\
>lo_dev) ) failed:

Message from syslogd@m at Feb  5 17:13:30 ...
 kernel:LustreError: 4289:0:(mdt_handler.c:2243:mdt_obj()) LBUG

Message from syslogd@m at Feb  5 17:13:30 ...
 kernel:Kernel panic - not syncing: LBUG