--- name: "mount.moosefs" section: "8" platform: "linux" package: "moosefs" version: "4.59.2-2" release: "Arch Linux 2026-11-01" platforms: ["linux"] url: "https://new.carta.tech/mfsmount/8" --- # mount.moosefs(8) mount MooseFS Part of [mfsmount(8)](/mfsmount/8.md). ## NAME mfsmount - mount MooseFS ## SYNOPSIS **mfsmount** \[*HOST*\[**:***PORT*\]**:**\[*PATH*\]\] \[options\] *mountpoint* **mfsmount** **-h**\|**--help** **mfsmount** **-V**\|**--version** Since 3.0.75 (Linux only): **mount -t moosefs** \[options\] \[*HOST*\[**:***PORT*\]**:**\[*PATH*\]\] *mountpoint* ## DESCRIPTION Mount MooseFS. ## OPTIONS ### GENERAL OPTIONS - **-h**, **--help** **display help and exit** - **-V** **display version information and exit** ### FUSE OPTIONS - **-d, -o debug** **enable debug mode (implies -f)** - **-f** **foreground operation** - **-s** **disable multi-threaded operation** ### MOOSEFS OPTIONS - **-c** *CFGFILE***, -o mfscfgfile=***CFGFILE* **loads file with additional mount options** - **-m, --meta, -o mfsmeta** **mount MFSMETA companion filesystem instead of primary MooseFS** - **-n** **omit default mount options (-o allow\_other)** - **-p** **prompt for password (interactive version of -o mfspassword=***PASS***)** - **-H** *HOST***, -o mfsmaster=***HOST* **connect with MooseFS master on** *HOST* **(default is mfsmaster)** - **-P** *PORT***, -o mfsport=***PORT* **connect with MooseFS master on** *PORT* **(default is 9421)** - **-B** *IP***, -o mfsbind=***IP* **local address to use for connecting with master instead of default one** - **-L** *IP***, -o mfsproxy=***IP* **define listen ip address of local master proxy for communication with tools (default: 127.0.0.1)** - **-S** *PATH***, -o mfssubfolder=***PATH* **mount specified MooseFS directory (default is /, i.e. whole filesystem)** - **-o mfspassword=***PASSWORD* **authenticate to MooseFS master with** *PASSWORD* - **-o mfspassfile=***FILENAME* **authenticate to MooseFS master with password stored in first line of file pointed by** *FILENAME* - **-o mfsmd5pass=***MD5* **authenticate to MooseFS master using directly given** *MD5* **(only if** **mfspassword option is not specified)** - **-o mfsdonotrememberpassword** **do not remember password in memory - more secure, but when session is lost then new session is created without password** - **-o mfsdebug** **print some MooseFS-specific debugging information** - **-o mfsmemlock** **try to lock memory (all allocated memory will be mapped to physical RAM - which also means no swapping)** - **-o allowoomkiller** **do not disable out of memory killer (Linux only)** - **-o mfslimitarenas=***N* **if N\>0 then limit glibc malloc arenas (Linux only - default: 4)** - **-o mfsflattrash** **use flat trash structure in meta (option added for compatibility reasons - since version 3.0.64 trash is split into 4096 subfolders which reduces problems with big trashes)** - **-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 mfsmkdircopysgid=***N* **sgid bit should be copied during mkdir operation (default depends on operating system)** - **-o mfssugidclearmode=***SMODE* **set sugid clear mode (see SUGID CLEAR MODES; default depends on operating system)** - **-o mfscachemode=***CMODE* **set cache mode (see DATA CACHE MODES; default is AUTO)** - **-o mfscachefiles** **(deprecated) preserve file data in cache (equivalent to '-o mfscachemode=YES')** - **-o mfsreaddirplusminto=***SEC* **set minimal entry/attributes cache timeout for readdirplus in seconds (default: 0.0001)** - **-o mfsattrcacheto=***SEC* **set attributes cache timeout in seconds (default: 1.0)** - **-o mfsxattrcacheto=***SEC* **set extended attributes (xattr) cache timeout in seconds (default: 30.0)** - **-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 mfsnegentrycacheto=***SEC* **set negative entry cache timeout in seconds (default: 0.0)** - **-o mfssymlinkcacheto=***SEC* **set symbolic link cache timeout in seconds (default: 300.0)** - **-o mfsgroupscacheto=***SEC* **set supplementary groups cache timeout in seconds (default: 300.0); setting this value to 0 disables supplementary groups support** - **-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 mfswritecachesize=***N* **specify write cache size in MiB (in range: 16..2048 - default: 256)** - **-o mfsreadaheadsize=***N* **define size of all read ahead buffers in MiB (in range: 16..2048 - default: 256)** - **-o mfsreadaheadleng=***N* **define amount of bytes to be additionally read (in range: 128KiB..2MiB - default: 1048576)** - **-o mfsreadaheadtrigger=***N* **define amount of bytes read sequentially that turns on read ahead (default: 10 \* mfsreadaheadleng)** - **-o mfserroronlostchunk** **when all known chunkservers are connected to the master and the required chunk is missing then immediately finish I/O and return an error** - **-o mfserroronnospace** **when all known chunkservers are connected to the master and there is no free space then immediately finish I/O and return an error** - **-o mfsioretries=***N* **specify number of retries before I/O error is returned (default: 30)** - **-o mfstimeout=***N* **define maximum timeout in seconds before I/O error is returned (default: 0 - which means no timeout)** - **-o mfslogretry=***N* **define minimal retry counter on which system will start log I/O messages (default: 5)** - **-o mfsfsyncmintime=***SEC* **force fsync before last file close when file was opened/created at least SEC seconds earlier (default: 0.0 - always do fsync before close)** - **-o mfspreflabels=***LABELEXPR* **specify preferred labels for choosing chunkservers during I/O** - **-o mfsnoxattrs** **turn off xattr support** - **-o mfsnoposixlocks** **turn off support for global posix locks (lockf + ioctl) - locks will work locally** - **-o mfsnobsdlocks** **turn off support for global BSD locks (flock) - locks will work locally** ### MOUNT OPTIONS **General mount options (see [mount(8)](/mount/8.md) 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.** ## FILES - **mfsmount.cfg** **configuration file for MooseFS mount daemon; refer to [mfsmount.cfg(5)](/mfsmount.cfg/5.md) manual for details** ## NOTES ### SUGID CLEAR MODE **During attribute change file systems sometimes clear flags suid and/or sgid.** **Behavior is different on different file systems.** **MFS tries to mimic behavior of most popular file system on given operating systems.** - **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)** ### DATA CACHE MODES **There are four cache modes: DIRECT, 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.** - **DIRECT** **forces direct io (bypasses cache)** - **NO,NONE or NEVER** **never allow files data to be kept in cache (safest but can reduce efficiency)** - **YES or ALWAYS** **always allow files data to be kept in cache (dangerous)** - **AUTO** **file cache is managed by mfsmaster automatically (should be very safe and efficient)** ### LABEL EXPRESSIONS **LABELEXPR grammar:** - *LABELEXPR* **-\>** *S* **;** *LABELEXPR* **\|** *S* - *S* **-\>** *S* **+** *M* **\|** *M* - *M* **-\>** *M* *L* **\|** *L* - *L* **-\> a .. z \| A .. Z \| (** *S* **) \| \[** *S* **\]** **Subexpressions should be placed in priority order. Up to nine subexpressions (priorities) can be specified.** ### FSTAB **On most Unix systems mfsmount can be invoked automatically from /etc/fstab. Be aware that rw or ro option has to be specified in** *options***. Also on many systems there should be option which informs the system that this mountpoint should be mounted after starting networking services (options such as \_netdev or late).** **Linux:** **mfsmount** *mountpoint* **fuse** *options* **0 0** **\*BSD:** **mfsmount\_magic** *mountpoint* **moosefs** *options***,mountprog=/usr/local/bin/mfsmount 0 0** **Since version 3.0.75 alternative form can be used:** **Linux:** *HOST***\[:***PORT***\]:\[***PATH***\]** *mountpoint* **moosefs** *options* **0 0** **\*BSD:** *HOST***\[:***PORT***\]:\[***PATH***\]** *mountpoint* **moosefs** *options***,mountprog=/usr/local/bin/mfsmount 0 0** ## REPORTING BUGS **Report bugs to \.** ## COPYRIGHT **Copyright (C) 2026 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 this program; if not, see** **\.** ## SEE ALSO [**mfsmaster**(8)](/mfsmaster/8.md), [**mfstools**(1)](/mfstools/1.md), [**mfsmount.cfg**(5)](/mfsmount.cfg/5.md), [**mount**(8)](/mount/8.md)