table of contents
- NAME
- SYNOPSIS
- DESCRIPTION
- OPTIONS
- SERVICE FORMATTING AND DELIMITERS
- INODE NUMBERS
- CACHE COHERENCY
- CIFS/NTFS ACL, SID/UID/GID MAPPING, SECURITY DESCRIPTORS
- ACCESSING FILES WITH BACKUP INTENT
- FILE AND DIRECTORY OWNERSHIP AND PERMISSIONS
- ENVIRONMENT VARIABLES
- NOTES
- CONFIGURATION
- BUGS
- VERSION
- SEE ALSO
- AUTHOR
MOUNT.CIFS(8) | System Administration tools | MOUNT.CIFS(8) |
NAME¶
mount.cifs - mount using the Common Internet File System (CIFS)SYNOPSIS¶
mount.cifs
{service} {mount-point} [-o options]
DESCRIPTION¶
This tool is part of the cifs-utils suite. mount.cifs mounts a Linux CIFS filesystem. It is usually invoked indirectly by the mount(8) command when using the "-t cifs" option. This command only works in Linux, and the kernel must support the cifs filesystem. The CIFS protocol is the successor to the SMB protocol and is supported by most Windows servers and many other commercial servers and Network Attached Storage appliances as well as by the popular Open Source server Samba. The mount.cifs utility attaches the UNC name (exported network resource) specified as service (using //server/share syntax, where "server" is the server name or IP address and "share" is the name of the share) to the local directory mount-point. Options to mount.cifs are specified as a comma-separated list of key=value pairs. It is possible to send options other than those listed here, assuming that the cifs filesystem kernel module (cifs.ko) supports them. Unrecognized cifs mount options passed to the cifs vfs kernel code will be logged to the kernel log. mount.cifs causes the cifs vfs to launch a thread named cifsd. After mounting it keeps running until the mounted resource is unmounted (usually via the umount utility).OPTIONS¶
user= argspecifies the username to connect as. If this
is not given, then the environment variable USER is used. This option
can also take the form "user%password" or "workgroup/user"
or "workgroup/user%password" to allow the password and workgroup to
be specified as part of the username.
Note
The cifs vfs accepts the parameter user=, or for users familiar with
smbfs it accepts the longer form of the parameter username=. Similarly
the longer smbfs style parameter names may be accepted as synonyms for the
shorter cifs parameters pass=,dom= and cred=.
password= arg
specifies the CIFS password. If this option is
not given then the environment variable PASSWD is used. If the password
is not specified directly or indirectly via an argument to mount,
mount.cifs will prompt for a password, unless the guest option is
specified.
Note that a password which contains the delimiter character (i.e. a comma
´,´) will fail to be parsed correctly on the command line. However,
the same password defined in the PASSWD environment variable or via a
credentials file (see below) or entered at the password prompt will be read
correctly.
credentials= filename
specifies a file that contains a username
and/or password and optionally the name of the workgroup. The format of the
file is:
This is preferred over having passwords in plaintext in a shared file, such as
/etc/fstab. Be sure to protect any credentials file properly.
uid= arg
username= value password= value domain= value
sets the uid that will own all files or
directories on the mounted filesystem when the server does not provide
ownership information. It may be specified as either a username or a numeric
uid. When not specified, the default is uid 0. The mount.cifs helper must be
at version 1.10 or higher to support specifying the uid in non-numeric form.
See the section on FILE AND DIRECTORY OWNERSHIP AND PERMISSIONS below for more
information.
forceuid
instructs the client to ignore any uid
provided by the server for files and directories and to always assign the
owner to be the value of the uid= option. See the section on FILE AND
DIRECTORY OWNERSHIP AND PERMISSIONS below for more information.
cruid= arg
sets the uid of the owner of the credentials
cache. This is primarily useful with sec=krb5. The default is the real uid of
the process performing the mount. Setting this parameter directs the upcall to
look for a credentials cache owned by that user.
gid= arg
sets the gid that will own all files or
directories on the mounted filesystem when the server does not provide
ownership information. It may be specified as either a groupname or a numeric
gid. When not specified, the default is gid 0. The mount.cifs helper must be
at version 1.10 or higher to support specifying the gid in non-numeric form.
See the section on FILE AND DIRECTORY OWNERSHIP AND PERMISSIONS below for more
information.
forcegid
instructs the client to ignore any gid
provided by the server for files and directories and to always assign the
owner to be the value of the gid= option. See the section on FILE AND
DIRECTORY OWNERSHIP AND PERMISSIONS below for more information.
port= arg
sets the port number on which the client will
attempt to contact the CIFS server. If this value is specified, look for an
existing connection with this port, and use that if one exists. If one doesn't
exist, try to create a new connection on that port. If that connection fails,
return an error. If this value isn't specified, look for an existing
connection on port 445 or 139. If no such connection exists, try to connect on
port 445 first and then port 139 if that fails. Return an error if both
fail.
servernetbiosname= arg
Specify the server netbios name (RFC1001 name)
to use when attempting to setup a session to the server. Although rarely
needed for mounting to newer servers, this option is needed for mounting to
some older servers (such as OS/2 or Windows 98 and Windows ME) since when
connecting over port 139 they, unlike most newer servers, do not support a
default server name. A server name can be up to 15 characters long and is
usually uppercased.
servern= arg
Synonym for servernetbiosname.
netbiosname= arg
When mounting to servers via port 139,
specifies the RFC1001 source name to use to represent the client netbios
machine name when doing the RFC1001 netbios session initialize.
file_mode= arg
If the server does not support the CIFS Unix
extensions this overrides the default file mode.
dir_mode= arg
If the server does not support the CIFS Unix
extensions this overrides the default mode for directories.
ip= arg
sets the destination IP address. This option
is set automatically if the server name portion of the requested UNC name can
be resolved so rarely needs to be specified by the user.
domain= arg
sets the domain (workgroup) of the user
guest
don´t prompt for a password
iocharset
Charset used to convert local path names to
and from Unicode. Unicode is used by default for network path names if the
server supports it. If iocharset is not specified then the nls_default
specified during the local client kernel build will be used. If server does
not support Unicode, this parameter is unused.
ro
mount read-only
rw
mount read-write
setuids
If the CIFS Unix extensions are negotiated
with the server the client will attempt to set the effective uid and gid of
the local process on newly created files, directories, and devices (create,
mkdir, mknod). If the CIFS Unix Extensions are not negotiated, for newly
created files and directories instead of using the default uid and gid
specified on the the mount, cache the new file´s uid and gid locally
which means that the uid for the file can change when the inode is reloaded
(or the user remounts the share).
nosetuids
The client will not attempt to set the uid and
gid on on newly created files, directories, and devices (create, mkdir, mknod)
which will result in the server setting the uid and gid to the default
(usually the server uid of the user who mounted the share). Letting the server
(rather than the client) set the uid and gid is the default.If the CIFS Unix
Extensions are not negotiated then the uid and gid for new files will appear
to be the uid (gid) of the mounter or the uid (gid) parameter specified on the
mount.
perm
Client does permission checks (vfs_permission
check of uid and gid of the file against the mode and desired operation), Note
that this is in addition to the normal ACL check on the target machine done by
the server software. Client permission checking is enabled by default.
noperm
Client does not do permission checks. This can
expose files on this mount to access by other users on the local client
system. It is typically only needed when the server supports the CIFS Unix
Extensions but the UIDs/GIDs on the client and server system do not match
closely enough to allow access by the user doing the mount. Note that this
does not affect the normal ACL check on the target machine done by the server
software (of the server ACL against the user name provided at mount
time).
dynperm
Instructs the server to maintain ownership and
permissions in memory that can´t be stored on the server. This
information can disappear at any time (whenever the inode is flushed from the
cache), so while this may help make some applications work, it´s behavior
is somewhat unreliable. See the section below on FILE AND DIRECTORY OWNERSHIP
AND PERMISSIONS for more information.
cache=
Cache mode. See the section below on CACHE
COHERENCY for details. Allowed values are:
directio
•none: do not cache file data at
all
•strict: follow the CIFS/SMB2 protocol
strictly
•loose: allow loose caching
semantics
The default in kernels prior to 3.7 was "loose". As of kernel 3.7 the
default is "strict".Do not do inode data caching on files opened
on this mount. This precludes mmaping files on this mount. In some cases with
fast networks and little or no caching benefits on the client (e.g. when the
application is doing large sequential reads bigger than page size without
rereading the same data) this can provide better performance than the default
behavior which caches reads (readahead) and writes (writebehind) through the
local Linux client pagecache if oplock (caching token) is granted and held.
Note that direct allows write operations larger than page size to be sent to
the server. On some kernels this requires the cifs.ko module to be built with
the CIFS_EXPERIMENTAL configure option.
This option is will be deprecated in 3.7. Users should use cache=none instead on
more recent kernels.
strictcache
Use for switching on strict cache mode. In
this mode the client reads from the cache all the time it has Oplock Level II,
otherwise - read from the server. As for write - the client stores a data in
the cache in Exclusive Oplock case, otherwise - write directly to the server.
This option is will be deprecated in 3.7. Users should use cache=strict instead
on more recent kernels.
rwpidforward
Forward pid of a process who opened a file to
any read or write operation on that file. This prevent applications like WINE
from failing on read and write if we use mandatory brlock style.
mapchars
Translate six of the seven reserved characters
(not backslash, but including the colon, question mark, pipe, asterik, greater
than and less than characters) to the remap range (above 0xF000), which also
allows the CIFS client to recognize files created with such characters by
Windows´s POSIX emulation. This can also be useful when mounting to most
versions of Samba (which also forbids creating and opening files whose names
contain any of these seven characters). This has no effect if the server does
not support Unicode on the wire. Please note that the files created with
mapchars mount option may not be accessible if the share is mounted without
that option.
nomapchars
Do not translate any of these seven characters
(default)
intr
currently unimplemented
nointr
(default) currently unimplemented
hard
The program accessing a file on the cifs
mounted file system will hang when the server crashes.
soft
(default) The program accessing a file on the
cifs mounted file system will not hang when the server crashes and will return
errors to the user application.
noacl
Do not allow POSIX ACL operations even if
server would support them.
The CIFS client can get and set POSIX ACLs (getfacl, setfacl) to Samba servers
version 3.0.10 and later. Setting POSIX ACLs requires enabling both CIFS_XATTR
and then CIFS_POSIX support in the CIFS configuration options when building
the cifs module. POSIX ACL support can be disabled on a per mount basis by
specifying "noacl" on mount.
cifsacl
This option is used to map CIFS/NTFS ACLs
to/from Linux permission bits, map SIDs to/from UIDs and GIDs, and get and set
Security Descriptors.
See sections on CIFS/NTFS ACL, SID/UID/GID MAPPING, SECURITY DESCRIPTORS
for more information.
backupuid= arg
Restrict access to files with the backup
intent to a user. Either a name or an id must be provided as an argument,
there are no default values.
See section ACCESSING FILES WITH BACKUP INTENT for more details
backupgid= arg
Restrict access to files with the backup
intent to a group. Either a name or an id must be provided as an argument,
there are no default values.
See section ACCESSING FILES WITH BACKUP INTENT for more details
nocase
Request case insensitive path name matching
(case sensitive is the default if the server suports it).
ignorecase
Synonym for nocase.
sec=
Security mode. Allowed values are:
If the server requires signing during protocol negotiation, then it may be
enabled automatically. Packet signing may also be enabled automatically if
it's enabled in /proc/fs/cifs/SecurityFlags.
nobrl
•none attempt to connection as a null
user (no name)
•krb5 Use Kerberos version 5
authentication
•krb5i Use Kerberos authentication and
forcibly enable packet signing
•ntlm Use NTLM password hashing
(default)
•ntlmi Use NTLM password hashing and
force packet signing
•ntlmv2 Use NTLMv2 password
hashing
•ntlmv2i Use NTLMv2 password hashing and
force packet signing
•ntlmssp Use NTLMv2 password hashing
encapsulated in Raw NTLMSSP message
•ntlmsspi Use NTLMv2 password hashing
encapsulated in Raw NTLMSSP message, and force packet signing
Do not send byte range lock requests to the
server. This is necessary for certain applications that break with cifs style
mandatory byte range locks (and most cifs servers do not yet support
requesting advisory byte range locks).
sfu
When the CIFS Unix Extensions are not
negotiated, attempt to create device files and fifos in a format compatible
with Services for Unix (SFU). In addition retrieve bits 10-12 of the mode via
the SETFILEBITS extended attribute (as SFU does). In the future the bottom 9
bits of the mode mode also will be emulated using queries of the security
descriptor (ACL). [NB: requires version 1.39 or later of the CIFS VFS. To
recognize symlinks and be able to create symlinks in an SFU interoperable form
requires version 1.40 or later of the CIFS VFS kernel module.
serverino
Use inode numbers (unique persistent file
identifiers) returned by the server instead of automatically generating
temporary inode numbers on the client. Although server inode numbers make it
easier to spot hardlinked files (as they will have the same inode numbers) and
inode numbers may be persistent (which is userful for some sofware), the
server does not guarantee that the inode numbers are unique if multiple server
side mounts are exported under a single share (since inode numbers on the
servers might not be unique if multiple filesystems are mounted under the same
shared higher level directory). Note that not all servers support returning
server inode numbers, although those that support the CIFS Unix Extensions,
and Windows 2000 and later servers typically do support this (although not
necessarily on every local server filesystem). Parameter has no effect if the
server lacks support for returning inode numbers or equivalent. This behavior
is enabled by default.
noserverino
Client generates inode numbers itself rather
than using the actual ones from the server.
See section INODE NUMBERS for more information.
nounix
Disable the CIFS Unix Extensions for this
mount. This can be useful in order to turn off multiple settings at once. This
includes POSIX acls, POSIX locks, POSIX paths, symlink support and retrieving
uids/gids/mode from the server. This can also be useful to work around a bug
in a server that supports Unix Extensions.
See section INODE NUMBERS for more information.
nouser_xattr
(default) Do not allow getfattr/setfattr to
get/set xattrs, even if server would support it otherwise.
rsize= bytes
Maximum amount of data that the kernel will
request in a read request in bytes. Prior to kernel 3.2.0, the default was
16k, and the maximum size was limited by the CIFSMaxBufSize module parameter.
As of kernel 3.2.0, the behavior varies according to whether POSIX extensions
are enabled on the mount and the server supports large POSIX reads. If they
are, then the default is 1M, and the maxmimum is 16M. If they are not
supported by the server, then the default is 60k and the maximum is around
127k. The reason for the 60k is because it's the maximum size read that
windows servers can fill. Note that this value is a maximum, and the client
may settle on a smaller size to accomodate what the server supports. In
kernels prior to 3.2.0, no negotiation is performed.
wsize= bytes
Maximum amount of data that the kernel will
send in a write request in bytes. Prior to kernel 3.0.0, the default and
maximum was 57344 (14 * 4096 pages). As of 3.0.0, the default depends on
whether the client and server negotiate large writes via POSIX extensions. If
they do, then the default is 1M, and the maximum allowed is 16M. If they do
not, then the default is 65536 and the maximum allowed is 131007.
Note that this value is just a starting point for negotiation in 3.0.0 and up.
The client and server may negotiate this size downward according to the
server's capabilities. In kernels prior to 3.0.0, no negotiation is performed.
It can end up with an existing superblock if this value isn't specified or
it's greater or equal than the existing one.
fsc
Enable local disk caching using FS-Cache for
CIFS. This option could be useful to improve performance on a slow link,
heavily loaded server and/or network where reading from the disk is faster
than reading from the server (over the network). This could also impact the
scalability positively as the number of calls to the server are reduced. But,
be warned that local caching is not suitable for all workloads, for e.g.,
read-once type workloads. So, you need to consider carefully the
situation/workload before using this option. Currently, local disk caching is
enabled for CIFS files opened as read-only.
NOTE: This feature is available only in the recent kernels that have been built
with the kernel config option CONFIG_CIFS_FSCACHE. You also need to have
cachefilesd daemon installed and running to make the cache operational.
multiuser
Map user accesses to individual credentials
when accessing the server. By default, CIFS mounts only use a single set of
user credentials (the mount credentials) when accessing a share. With this
option, the client instead creates a new session with the server using the
user's credentials whenever a new user accesses the mount. Further accesses by
that user will also use those credentials. Because the kernel cannot prompt
for passwords, multiuser mounts are limited to mounts using sec= options that
don't require passwords.
With this change, it's feasible for the server to handle permissions
enforcement, so this option also implies "noperm". Furthermore, when
unix extensions aren't in use and the administrator has not overriden
ownership using the uid= or gid= options, ownership of files is presented as
the current user accessing the share.
actimeo= arg
The time (in seconds) that the CIFS client
caches attributes of a file or directory before it requests attribute
information from a server. During this period the changes that occur on the
server remain undetected until the client checks the server again.
By default, the attribute cache timeout is set to 1 second. This means more
frequent on-the-wire calls to the server to check whether attributes have
changed which could impact performance. With this option users can make a
tradeoff between performance and cache metadata correctness, depending on
workload needs. Shorter timeouts mean better cache coherency, but frequent
increased number of calls to the server. Longer timeouts mean a reduced number
of calls to the server but looser cache coherency. The actimeo value is a
positive integer that can hold values between 0 and a maximum value of 2^30 *
HZ (frequency of timer interrupt) setting.
noposixpaths
If unix extensions are enabled on a share,
then the client will typically allow filenames to include any character
besides '/' in a pathname component, and will use forward slashes as a
pathname delimiter. This option prevents the client from attempting to
negotiate the use of posix-style pathnames to the server.
posixpaths
Inverse of noposixpaths.
prefixpath=
It's possible to mount a subdirectory of a
share. The preferred way to do this is to append the path to the UNC when
mounting. However, it's also possible to do the same by setting this option
and providing the path there.
--verbose
Print additional debugging information for the
mount. Note that this parameter must be specified before the -o. For example:
mount -t cifs //server/share /mnt --verbose -o user=username
SERVICE FORMATTING AND DELIMITERS¶
It´s generally preferred to use forward slashes (/) as a delimiter in service names. They are considered to be the "universal delimiter" since they are generally not allowed to be embedded within path components on Windows machines and the client can convert them to blackslashes (\) unconditionally. Conversely, backslash characters are allowed by POSIX to be part of a path component, and can´t be automatically converted in the same way. mount.cifs will attempt to convert backslashes to forward slashes where it´s able to do so, but it cannot do so in any path component following the sharename.INODE NUMBERS¶
When Unix Extensions are enabled, we use the actual inode number provided by the server in response to the POSIX calls as an inode number. When Unix Extensions are disabled and "serverino" mount option is enabled there is no way to get the server inode number. The client typically maps the server-assigned "UniqueID" onto an inode number. Note that the UniqueID is a different value from the server inode number. The UniqueID value is unique over the scope of the entire server and is often greater than 2 power 32. This value often makes programs that are not compiled with LFS (Large File Support), to trigger a glibc EOVERFLOW error as this won´t fit in the target structure field. It is strongly recommended to compile your programs with LFS support (i.e. with -D_FILE_OFFSET_BITS=64) to prevent this problem. You can also use "noserverino" mount option to generate inode numbers smaller than 2 power 32 on the client. But you may not be able to detect hardlinks properly.CACHE COHERENCY¶
With a network filesystem such as CIFS or NFS, the client must contend with the fact that activity on other clients or the server could change the contents or attributes of a file without the client being aware of it. One way to deal with such a problem is to mandate that all file accesses go to the server directly. This is performance prohibitive however, so most protocols have some mechanism to allow the client to cache data locally. The CIFS protocol mandates (in effect) that the client should not cache file data unless it holds an opportunistic lock (aka oplock) or a lease. Both of these entities allow the client to guarantee certain types of exclusive access to a file so that it can access its contents without needing to continually interact with the server. The server will call back the client when it needs to revoke either of them and allow the client a certain amount of time to flush any cached data. The cifs client uses the kernel's pagecache to cache file data. Any I/O that's done through the pagecache is generally page-aligned. This can be problematic when combined with byte-range locks as Windows' locking is mandatory and can block reads and writes from occurring. cache=none means that the client never utilizes the cache for normal reads and writes. It always accesses the server directly to satisfy a read or write request. cache=strict means that the client will attempt to follow the CIFS/SMB2 protocol strictly. That is, the cache is only trusted when the client holds an oplock. When the client does not hold an oplock, then the client bypasses the cache and accesses the server directly to satisfy a read or write request. By doing this, the client avoids problems with byte range locks. Additionally, byte range locks are cached on the client when it holds an oplock and are "pushed" to the server when that oplock is recalled. cache=loose allows the client to use looser protocol semantics which can sometimes provide better performance at the expense of cache coherency. File access always involves the pagecache. When an oplock or lease is not held, then the client will attempt to flush the cache soon after a write to a file. Note that that flush does not necessarily occur before a write system call returns. In the case of a read without holding an oplock, the client will attempt to periodically check the attributes of the file in order to ascertain whether it has changed and the cache might no longer be valid. This mechanism is much like the one that NFSv2/3 use for cache coherency, but it particularly problematic with CIFS. Windows is quite "lazy" with respect to updating the "LastWriteTime" field that the client uses to verify this. The effect is that cache=loose can cause data corruption when multiple readers and writers are working on the same files. Because of this, when multiple clients are accessing the same set of files, then cache=strict is recommended. That helps eliminate problems with cache coherency by following the CIFS/SMB2 protocols more strictly. Note too that no matter what caching model is used, the client will always use the pagecache to handle mmap'ed files. Writes to mmap'ed files are only guaranteed to be flushed to the server when msync() is called, or on close(). The default in kernels prior to 3.7 was "loose". As of 3.7, the default is "strict".CIFS/NTFS ACL, SID/UID/GID MAPPING, SECURITY DESCRIPTORS¶
This option is used to work with file objects which posses Security Descriptors and CIFS/NTFS ACL instead of UID, GID, file permission bits, and POSIX ACL as user authentication model. This is the most common authentication model for CIFS servers and is the one used by Windows.•http://technet.microsoft.com/en-us/library/bb463216.aspx
•a kernel upcall to the cifs.idmap
utility set up via request-key.conf(5)
•winbind support configured via
nsswitch.conf(5) and smb.conf(5)
Please refer to the respective manpages of cifs.idmap(8) and winbindd(8) for
more information.
•There may be an increased latency when
handling metadata due to additional requests to get and set security
descriptors.
•The mapping between a CIFS/NTFS ACL and
POSIX file permission bits is imperfect and some ACL information may be lost
in the translation.
•If either upcall to cifs.idmap is not
setup correctly or winbind is not configured and running, ID mapping will
fail. In that case uid and gid will default to either to those values of the
share or to the values of uid and/or gid mount options if specified.
ACCESSING FILES WITH BACKUP INTENT¶
For an user on the server, desired access to a file is determined by the permissions and rights associated with that file. This is typically accomplished using owenrship and ACL. For a user who does not have access rights to a file, it is still possible to access that file for a specific or a targeted purpose by granting special rights. One of the specific purposes is to access a file with the intent to either backup or restore i.e. backup intent. The right to access a file with the backup intent can typically be granted by making that user a part of the built-in group Backup Operators. Thus, when this user attempts to open a file with the backup intent, open request is sent by setting the bit FILE_OPEN_FOR_BACKUP_INTENT as one of the CreateOptions.FILE AND DIRECTORY OWNERSHIP AND PERMISSIONS¶
The core CIFS protocol does not provide unix ownership information or mode for files and directories. Because of this, files and directories will generally appear to be owned by whatever values the uid= or gid= options are set, and will have permissions set to the default file_mode and dir_mode for the mount. Attempting to change these values via chmod/chown will return success but have no effect. When the client and server negotiate unix extensions, files and directories will be assigned the uid, gid, and mode provided by the server. Because CIFS mounts are generally single-user, and the same credentials are used no matter what user accesses the mount, newly created files and directories will generally be given ownership corresponding to whatever credentials were used to mount the share. If the uid´s and gid´s being used do not match on the client and server, the forceuid and forcegid options may be helpful. Note however, that there is no corresponding option to override the mode. Permissions assigned to a file when forceuid or forcegid are in effect may not reflect the the real permissions. When unix extensions are not negotiated, it´s also possible to emulate them locally on the server using the "dynperm" mount option. When this mount option is in effect, newly created files and directories will receive what appear to be proper permissions. These permissions are not stored on the server however and can disappear at any time in the future (subject to the whims of the kernel flushing out the inode cache). In general, this mount option is discouraged. It´s also possible to override permission checking on the client altogether via the noperm option. Server-side permission checks cannot be overriden. The permission checks done by the server will always correspond to the credentials used to mount the share, and not necessarily to the user who is accessing the share.ENVIRONMENT VARIABLES¶
The variable USER may contain the username of the person to be used to authenticate to the server. The variable can be used to set both username and password by using the format username%password. The variable PASSWD may contain the password of the person using the client. The variable PASSWD_FILE may contain the pathname of a file to read the password from. A single line of input is read and used as the password.NOTES¶
This command may be used only by root, unless installed setuid, in which case the noeexec and nosuid mount flags are enabled. When installed as a setuid program, the program follows the conventions set forth by the mount program for user mounts, with the added restriction that users must be able to chdir() into the mountpoint prior to the mount in order to be able to mount onto it. Some samba client tools like smbclient(8) honour client-side configuration parameters present in smb.conf. Unlike those client tools, mount.cifs ignores smb.conf completely.CONFIGURATION¶
The primary mechanism for making configuration changes and for reading debug information for the cifs vfs is via the Linux /proc filesystem. In the directory /proc/fs/cifs are various configuration files and pseudo files which can display debug information. There are additional startup options such as maximum buffer size and number of buffers which only may be set when the kernel cifs vfs (cifs.ko module) is loaded. These can be seen by running the modinfo utility against the file cifs.ko which will list the options that may be passed to cifs during module installation (device driver load). For more information see the kernel file fs/cifs/README.BUGS¶
Mounting using the CIFS URL specification is currently not supported. The credentials file does not handle usernames or passwords with leading space. Note that the typical response to a bug report is a suggestion to try the latest version first. So please try doing that first, and always include which versions you use of relevant software when reporting bugs (minimum: mount.cifs (try mount.cifs -V), kernel (see /proc/version) and server type you are trying to contact.VERSION¶
This man page is correct for version 1.74 of the cifs vfs filesystem (roughly Linux kernel 3.0).SEE ALSO¶
Documentation/filesystems/cifs.txt and fs/cifs/README in the linux kernel source tree may contain additional options and information. cifs.upcall(8)AUTHOR¶
Steve French The syntax and manpage were loosely based on that of smbmount. It was converted to Docbook/XML by Jelmer Vernooij. The maintainer of the Linux cifs vfs and the userspace tool mount.cifs is Steve French. The Linux CIFS Mailing list is the preferred place to ask questions regarding these programs.02/07/2010 | cifs-utils |