mount.cifs
8
mount.cifs
mount using the Common Internet File System (CIFS)
mount.cifs
service
mount-point
-o options
DESCRIPTION
This tool is part of the samba
7 suite.
mount.cifs mounts a Linux CIFS filesystem. It
is usually invoked indirectly by
the mount8 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) to
the local directory mount-point. It is possible to set the mode for mount.cifs to
setuid root to allow non-root users to mount shares to directories for which they
have write permission.
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 cifs filesystem 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=arg
specifies 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 "user/workgroup" or
"user/workgroup%password" to allow the password and workgroup
to be specified as part of the username.
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) will be read correctly.
credentials=filename
specifies a file that contains a username
and/or password. The format of the file is:
username=value
password=value
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
sets the uid that will own all files on
the mounted filesystem.
It may be specified as either a username or a numeric uid.
This parameter is ignored when the target server supports
the CIFS Unix extensions.
gid=arg
sets the gid that will own all files on
the mounted filesystem.
It may be specified as either a groupname or a numeric
gid. This parameter is ignored when the target server supports
the CIFS Unix extensions.
port=arg
sets the port number on the server to attempt to contact to negotiate
CIFS support. If the CIFS server is not listening on this port or
if it is not specified, the default ports will be tried i.e.
port 445 is tried and if no response then port 139 is tried.
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 host or IP address.
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
rsize
default network read size
wsize
default network write size
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.
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.
For more information see the kernel file fs/cifs/README.
BUGS
Passwords and other options containing , can not be handled.
For passwords an alternative way of passing them is in a credentials
file or in the PASSWD environment.
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 1.0.6 of
the cifs vfs filesystem (roughly Linux kernel 2.6.6).
SEE ALSO
Documentation/filesystems/cifs.txt and fs/cifs/README in the linux kernel
source tree may contain additional options and information.
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.