NAME

       mfsbdev - MooseFS block device daemon/management tool

SYNOPSIS

       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]
       [-i]

       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]

DESCRIPTION

       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.

COMMANDS

       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)

OPTIONS

       -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
       name

       -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)

       -i  -  ignore  locks;  one  file  may  be  mapped  to more than one block device, each map
       operation will try to obtain the appropriate lock (shared for ro, exclusive  for  rw)  but
       will succed even if the lock is not obtained

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

EXAMPLES

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

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

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

       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
       /dev/mfs/mytestvm).

REPORTING BUGS

       Report bugs to <bugs@moosefs.com>.

COPYRIGHT

       Copyright (C) 2023 Jakub Kruszona-Zawadzki, Saglabs SA

       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 http://www.gnu.org/licenses/gpl-2.0.html

SEE ALSO

       mfsmount(8)