Создаю РАМ диск. Создаю на нём ЛВМ. Начинаю создавать файловую систему.
Ext4 - создаёт успешно.
mkfs.xfs -f /dev/... - несоздаёт, и код возврата ноль!!

Что неправильно делаю? Куда копать? Под ЦентОС 7 тоже самое работало, под Убунту 16.04 - нет.

Спасибо!

Вот как создаю ФС:

me: ~ $ sudo mkfs.ext4 /dev/developGRP/developVLM 

me: ~ $ sudo mkfs.xfs -f /dev/developGRP/developVLM
meta-data=/dev/developGRP/developVLM isize=512    agcount=2, agsize=7680 blks
         =                       sectsz=4096  attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=0
data     =                       bsize=4096   blocks=15360, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal log           bsize=4096   blocks=1605, version=2
         =                       sectsz=4096  sunit=1 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

me: ~ $ echo $?
0

me: ~ $ sudo mount /dev/developGRP/developVLM /mnt
mount: wrong fs type, bad option, bad superblock on /dev/mapper/developGRP-developVLM,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail or so.

me: ~ $ echo $?
32

Вот скрипт создания RAM диска и LVM:

#!/bin/bash
set -x
set -e
declare -r blckDev="/dev/ram0"
declare -r name_vg="developGRP"
declare -r name_lv="developVLM"
if ! egrep "^brd[[:space:]]" /proc/modules ; then
    modprobe brd max_part=10 rd_size=128000 # Size is in kb by default.
fi
test -b "${blckDev}"
if ! pvs "${blckDev}" ; then
    pvcreate "${blckDev}"
fi
if ! vgs "${name_vg}" ; then
    vgcreate "${name_vg}" "${blckDev}"
fi
if ! lvs "${name_vg}/${name_lv}" ; then
    lvcreate --extents "50%FREE" --name "${name_lv}" "${name_vg}" "${blckDev}"
fi
vgscan --mknodes --cache

Вот логи из консоли, как всё запускалось, коды возврата:

me: ~ $ sudo bash create-LVM-point.sh                     
[sudo] password for me: 
+ set -e
+ declare -r blckDev=/dev/ram0
+ declare -r name_vg=developGRP
+ declare -r name_lv=developVLM
+ egrep '^brd[[:space:]]' /proc/modules
+ modprobe brd max_part=10 rd_size=128000
+ test -b /dev/ram0
+ pvs /dev/ram0
  Failed to find physical volume "/dev/ram0".
+ pvcreate /dev/ram0
  Physical volume "/dev/ram0" successfully created
+ vgs developGRP
  Volume group "developGRP" not found
  Cannot process volume group developGRP
+ vgcreate developGRP /dev/ram0
  Volume group "developGRP" successfully created
+ lvs developGRP/developVLM
  Failed to find logical volume "developGRP/developVLM"
+ lvcreate --extents 50%FREE --name developVLM developGRP /dev/ram0
  Logical volume "developVLM" created.
+ vgscan --mknodes --cache
  Reading all physical volumes.  This may take a while...
  Found volume group "developGRP" using metadata type lvm2
/home/and/Data/coding_mbb/fs-size-change/src/create-LVM.sh: line 29: syntax error near unexpected token `fi'
me: ~ $ sudo lvs
  LV         VG         Attr       LSize  Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  developVLM developGRP -wi-a----- 60,00m                                                    
me: ~ $ sudo mkfs.ext4 /dev/
Display all 234 possibilities? (y or n)
me: ~ $ sudo mkfs.ext4 /dev/developGRP/developVLM 
mke2fs 1.42.13 (17-May-2015)
Discarding device blocks: done                            
Creating filesystem with 61440 1k blocks and 15360 inodes
Filesystem UUID: 44d47ca1-cd57-49ca-8b53-fd4e94482bfc
Superblock backups stored on blocks: 
        8193, 24577, 40961, 57345
Allocating group tables: done                            
Writing inode tables: done                            
Creating journal (4096 blocks): done
Writing superblocks and filesystem accounting information: done
me: ~ $ sudo mount /dev/developGRP/developVLM /mnt
me: ~ $ sudo umount /mnt
me: ~ $ sudo mkfs.xfs -f /dev/developGRP/developVLM 
meta-data=/dev/developGRP/developVLM isize=512    agcount=2, agsize=7680 blks
         =                       sectsz=4096  attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=0
data     =                       bsize=4096   blocks=15360, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal log           bsize=4096   blocks=1605, version=2
         =                       sectsz=4096  sunit=1 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
me: ~ $ echo $?
0
me: ~ $ sudo mount /dev/developGRP/developVLM /mnt
mount: wrong fs type, bad option, bad superblock on /dev/mapper/developGRP-developVLM,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail or so.
me: ~ $ echo $?
32

P.S. Компьютер перезагружал... Если чего...