Provided by: moosefs-client_3.0.116-1ubuntu2_amd64 bug


       mfsbdev - MooseFS block device daemon/management tool


       mfsbdev  start  [-H  masterhost]  [-P  masterport] [-S masterpath] [-p masterpassword | -x
       passwordfile] [-l linksocket] [-F]

       mfsbdev stop [-l linksocket]

       mfsbdev map [-l linksocket] -f mfsfile [-d nbddevice] [-n linkname] [-s bdevsize] [-r]

       mfsbdev unmap [-l linksocket] ( -f mfsfile | -d nbddevice | -n linkname )

       mfsbdev list [-l linksocket] [-t m|u]

       mfsbdev resize [-l linksocket] ( -f mfsfile | -d nbddevice | -n linkname ) [-s bdevsize]


       This tool is used to manage block devices. This tool works in Linux  ONLY.  Kernel  module
       nbd must be loaded for this tool to work properly.


       start  -  starts  the  daemon;  the daemon only listens on a socket at this point; all the
       other commands use the socket to communicate with the daemon; if no  socket  is  specified
       via -l option, the default is used: /dev/mfs/nbdsock

       stop - stops the daemon

       map - maps a file on mfs to be used as a block device

       unmap - removes a mapping

       list - lists current mappings

       resize - changes the size of a block device (requires kernel version 4.18 or higher)


       -H - master host; default is 'mfsmaster'

       -P - master port; default is '9421'

       -S  -  master  path  (subfolder  in  MFS  that will be used as a root for all block device
       mappings); default is '/'

       -p - master password; mutually exclusive  with  -x  option;  if  neither  -p  nor  -x  are
       supplied, the tool tries to connect without a password

       -x  -  path  to  a  file containing master password; mutually exclusive with -p option; if
       neither -p nor -x are supplied, the tool tries to connect without a password

       -l - path to communication socket; default is /dev/mfs/nbdsock

       -F - do not daemonize the tool (run in foreground)

       -f - path to mfs file used to map block device;

       -d - path to network block device ('/dev/nbdX'); by default  (if  this  parameter  is  not
       supplied) first available device is used with the map command

       -n  -  name  of  symbolic link created in '/dev/mfs', pointing at the network block device
       created by the map command; default is a combination of master hostname, port and mfs file

       -s  -  size of the block device, both SI and IEC suffixes can be used; default is the size
       of the file the block device is mapped to

       -r - maps block device as readonly (allows multiple mappings of the same file)

       -t - forces the list command to display information in a format ready to use with  map  (m
       parameter) or unmap (u parameter) command


       mfsbdev  start - start nbd daemon with default options (masterhost = mfsmaster, masterport
       = 9421, linksocket = /dev/mfs/nbdsock, authentication without password)

       mfsbdev start -H -P 9521 -x /etc/mfs/mastersecret - start  nbd  daemon
       that will connect to master on port 9521 using password read from file

       mfsbdev stop -l /tmp/mynbdinstance - stop nbd daemon using for communication  unix  socket

       mfsbdev  map  -f  devices/mybdev1.bin -s 2Ti -n mytestvm - add mapping to daemon using for
       communication default socket (/dev/mfs/nbdsock). Device will  be  assigned  automatically,
       file  devices/mybdev1.bin  will be mapped to this device, link '/dev/mfs/mytestvm' to this
       device will be created and block device will have size of 2TiB.

       mfsbdev unmap -n mytestvm - remove  mapping  that  has  link  named  mytestvm  (uses  link


       Report bugs to <>.


       Copyright (C) 2021 Jakub Kruszona-Zawadzki, Core Technology Sp. z o.o.

       This file is part of MooseFS.

       MooseFS  is free software; you can redistribute it and/or modify it under the terms of the
       GNU General Public License as published by the Free Software Foundation, version 2 (only).

       MooseFS is distributed in the hope that it will  be  useful,  but  WITHOUT  ANY  WARRANTY;
       without  even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
       See the GNU General Public License for more details.

       You should have received a copy of the GNU General Public License along with  MooseFS;  if
       not,  write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
       02111-1301, USA or visit