mfsmount(1) mount Lizard File System


mfsmount mountpoint [-d] [-f] [-s] [-m] [-n] [-p]
[-H HOST] [-P PORT] [-S PATH] [-o opt[,opt]...]

mfsmount -h|--help

mfsmount -V|--version


Mount Lizard File System.

General options:

-h, --help

display help and exit


display version information and exit

FUSE options:

-d, -o debug

enable debug mode (implies -f)


foreground operation


disable multi-threaded operation

LizardFS options:

-c CFGFILE, -o mfscfgfile=CFGFILE

loads file with additional mount options

-m, --meta, -o mfsmeta

mount MFSMETA companion filesystem instead of primary LizardFS


omit default mount options (-o allow_other,default_permissions)


prompt for password (interactive version of -o mfspassword=PASS)

-H HOST, -o mfsmaster=HOST

connect with LizardFS master on HOST (default is mfsmaster)

-P PORT, -o mfsport=PORT

connect with LizardFS master on PORT (default is 9421)

-B HOST, -o mfsbind=HOST

local address to use for connecting with master instead of default one

-S PATH, -o mfssubfolder=PATH

mount specified LizardFS directory (default is /, i.e. whole filesystem)

-o enablefilelocks=[0,1]

enables/disables global file locking (disabled by default)

-o mfspassword=PASSWORD

authenticate to LizardFS master with PASSWORD

-o mfsmd5pass=MD5

authenticate to LizardFS master using directly given MD5 (only if mfspassword option is not specified)

-o mfsdelayedinit

connection with master is done in background - with this option mount can be run without network (good for being run from fstab / init scripts etc.)

-o mfsacl

enable ACL support (disabled by default)

-o mfsaclcacheto=SEC

set ACL cache timeout in seconds (default: 1.0)

-o mfsaclcachesize=N

define ACL cache size in number of entries (0: no cache; default: 1000)

-o mfsrwlock=0|1

when set to 1, parallel reads from the same descriptor are performed (default: 1)

-o mfsmkdircopysgid=N

sgid bit should be copied during mkdir operation (on linux default: 1, otherwise: 0)

-o mfssugidclearmode=SMODE

set sugid clear mode (see below)

-o mfsdebug

print some LizardFS-specific debugging information

-o mfscachemode=CACHEMODE

set cache mode (see DATA CACHE MODES; default is AUTO)

-o mfscachefiles

(deprecated) preserve file data in cache (equivalent to -o mfscachemode=YES)

-o mfsattrcacheto=SEC

set attributes cache timeout in seconds (default: 1.0)

-o mfsentrycacheto=SEC

set file entry cache timeout in seconds (default: 0.0, i.e. no cache)

-o mfsdirentrycacheto=SEC

set directory entry cache timeout in seconds (default: 1.0)

-o mfswritecachesize=N

specify write cache size in MiB (in range: 16..2048 - default: 128)

-o mfscacheperinodepercentage=N

specify what part of the write cache non occupied by other inodes can a single inode occupy (measured in %). E.g. When N=75 and the inode X uses 10 MiB, and all other inodes use 20 MiB out of 100 MiB cache, X can use 50 MiB more (since 75% of 80 MiB is 60 MiB). Default: 25.

-o mfschunkserverreadto=MSEC

set timeout for whole communication with a chunkserver during read operation in milliseconds (default: 2000)

-o mfschunkserverwriteto=MSEC

set chunkserver response timeout during write operation in milliseconds (default: 5000)

-o mfschunkserverrtt=MSEC

set timeout after which SYN packet is considered lost during the first retry of connecting a chunkserver (default: 200)

-o mfschunkserverconnectreadto=MSEC

set timeout for connecting with chunkservers during read operation in milliseconds (default: 2000)

-o mfschunkserverbasicreadto=MSEC

set timeout for executing the basic variant of a read operation in milliseconds (default: 2000)

-o mfschunkservertotalreadto=MSEC

set timeout for the whole communication with chunkservers during a read operation in milliseconds (default: 2000)

-o mfsrlimitnofile=N

try to change limit of simultaneously opened file descriptors on startup (default: 100000)

-o mfsnice=LEVEL

try to change nice level to specified value on startup (default: -19)

-o mfswriteworkers=N

define number of write workers (default: 10)

-o mfswritewindowsize=N

define write window size (in blocks) for each chunk (default: 15)

-o mfsmemlock

try to lock memory (must be enabled at build time)

-o mfsdonotrememberpassword

do not remember password in memory - more secure, but when session is lost then new session is created without password

-o mfsioretries=N

specify number of retries before I/O error is returned (default: 30)

-o mfsreportreservedperiod=N

specify interval of reporting reserved inodes in seconds (default: 60)

-o mfsiolimits=PATH

specify local I/O limiting configuration file (default: no I/O limiting)

General mount options (see mount(8) manual):

-o rw|-o ro

Mount file-system in read-write (default) or read-only mode respectively.

-o suid|-o nosuid

Enable or disable suid/sgid attributes to work.

-o dev|-o nodev

Enable or disable character or block special device files interpretation.

-o exec|-o noexec

Allow or disallow execution of binaries.

-o symlinkcachetimeout=N

Set timeout value for symlink cache timeout in seconds. Default value is 3600.


There are three cache modes: NO, YES and AUTO. Default option is AUTO and you shuldn't change it unless you really know what you are doing. In AUTO mode data cache is managed automatically by mfsmaster.


never allow files data to be kept in cache (safest but can reduce efficiency)


always allow files data to be kept in cache (dangerous)


file cache is managed by mfsmaster automatically (should be very safe and efficient)


SMODE can be set to:

NEVER - MFS will not change suid and sgid bit on chown

ALWAYS - clear suid and sgid on every chown - safest operation

OSX - standard behavior in OS X and Solaris (chown made by unprivileged user clear suid and sgid)

BSD - standard behavior in BSD systems (like in OSX, but only when something is really changed)

EXT - standard behavior in most file systems on Linux (directories not changed, others: suid cleared always, sgid only when group exec bit is set)

XFS - standard behavior in XFS on Linux (like EXT but directories are changed by unprivileged users)

SMODE extra info:

btrfs,ext2,ext3,ext4,hfs[+],jfs,ntfs and reiserfs on Linux work as EXT.

Only xfs on Linux works a little different. Beware that there is a strange operation - chown(-1,-1) which is usually converted by a kernel into something like chmod ug-s, and therefore can't be controlled by MFS as chown


Report bugs to <[email protected]>.


Copyright 2008-2009 Gemius SA, 2013-2015 Skytechnology sp. z o.o.

LizardFS 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 3.

LizardFS 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 LizardFS. If not, see