I discussed FreeBSD's SMB filesystem support well over a year ago. At the time, it was highly experimental and suffered occasional seizures.
It has since improved to the point where it is reliable enough for use in production settings. If you want to access a Windows share from your FreeBSD workstation, this is how you do it. Before you start, gather some basic information about your Windows network.
ipconfig /allon a Windows system.)
The first problem you have is supporting the multiple character sets
so common in Windows. It's very easy for a Windows user to use
characters not found in the standard ASCII alphabet. You don't want
to dump such a character into your kernel; you'll only confuse it, and
a confused kernel is not a happy kernel. The FreeBSD kernel does not
include the libraries to handle this. Install the
libiconv port from
/usr/ports/converters/libiconv before you proceed. Note that
is under the LGPL; if you're interested in using SMBFS in an embedded
system, run this by your legal department.
Now recompile your kernel to handle SMB. Just add the following options to your kernel.
options NETSMB options NETSMBCRYPTO options LIBMCHAIN options LIBICONV options SMBFS
The SMBFS kernel option is also available as a module. Because you already must rebuild your kernel to include SMB networking support, however, you might as well compile it statically.
Once you have the kernel built, install the SMB tools from
/usr/ports/net/smbfs. The SMB tools must be exactly synchronized with
your kernel. This makes packages mostly useless, unless you have
several identical machines. If you upgrade your FreeBSD install, you
must upgrade the port. To make life somewhat more difficult, the
master SMBFS source code repository lurks behind a very slow link in
Kazakhstan. I recommend that you store the distribution file somewhere on your
network, so you can easily rebuild the tools without having to re-fetch
the source from the other side of the world.
The SMB tools use a configuration file, either
/usr/local/etc/nsmb.conf. Any settings in
nsmb.conf override settings
in user home directories. The configuration file is divided into
sections by labels in angle brackets. For example, settings that
apply to every SMB connection are kept in the
[default] section. You can create your own sections by specifying servers, users, and share,
in one of the following formats.
[servername] [servername:username] [servername:username:sharename]
For example, information that applies to an entire server goes in a
section named after the server. Information that applies to a
specific user is kept in a user name section, and information that only
applies to a single share is kept in a label that includes the
share name. You could lump the information for all the shares under a
[servername] entry if you don't have more specific information per
These values are all SMB values -- i.e., my Windows user name is
"mlucas", but my Unix user name is "mwlucas", so I use "mlucas" in
You use keywords to assign a configuration to a section. Some keywords can only be used in particular sections. For example, servers have IP addresses, users don't. You assign a value with an equal sign, such as "keyword=value". Here are the keywords.
This is the name of the NT domain or Windows workgroup you want to access.
This is the IP (or IPX) address of a SMB server with this name. This
can only appear under a plain
This handles conversions between the character set used on the FreeBSD system and the character set used on the SMB server. (As SMBFS was written in Central Asia, this was a matter of no small concern!)
This is the IP address of the NetBIOS (WINS) name server. You can put
this in the
[default] section or under a particular
This is the NetBIOS scope. If you don't know what NetBIOS scope is, you probably don't need to set it.
This is the number of times the SMB client will try to contact the server before assuming that the connection has broken. The default is probably fine.
This is the length of time the system will wait for a response to a SMB request. Again, the default is probably fine.
This is a clear-text password for a user or a share. If you
must store passwords in
So, let's start setting up a basic
nsmb.conf file. First, we want to
be able to find hosts. For this we need a workgroup and a NetBIOS
name server. I also have the same user name across the entire domain,
so I'm going to put my user name in the
[default] workgroup=EXAMPLE nbns=192.168.2.80 username=mlucas
With this information, you should be able to perform basic SMB name
smbutil(1) can perform basic NetBIOS name resolution.
# smbutil lookup fileserv4 Got response from 192.168.2.80 IP address of fileserv4: 192.168.1.202 #
If this works, you have basic SMB functionality. Now we want to
access a share on that system. Before you can query a host, you must
log in to it. Only root can use these
# smbutil login //mlucas@fileserv4 Password: Connected to MLUCAS #
So, our password is correct. Let's see what resources this server offers.
# smbutil view //mlucas@fileserv4 Password: Share Type Comment ------------------------------- jsmith$ disk gdonner$ disk mlucas$ disk ...
You'll get a list of every shared resource on the SMB server. When finished, log out of the host.
# smbutil logout //mlucas@fileserv4 Password: Connection unmarked as permanent and will be closed when possible #
Now that you've finished investigating, let's actually mount a share
mount_smbfs(8). The syntax is very simple.
mount_smbfs //username@servername/share /mount/point
To mount my personal fileserver share on
# mount_smbfs //mlucas@fileserv4/mlucas /home/mwlucas/smbmount
Check your work with
#df Filesystem 1K-blocks Used Avail Capacity Mounted on /dev/ad0s1a 99183 49105 42144 54% / /dev/ad0s1f 5186362 3091500 1679954 65% /usr /dev/ad0s1e 198399 22816 159712 12% /var procfs 4 4 0 100% /proc //MLUCAS@FILESERV4/MLUCAS 128000 54320 73680 42% /usr/home/mwlucas/smbmount #
I can now do basic file operations, including using emacs and
StarOffice on the documents in this folder. Life just got a little
mount_smbfs includes several options to fine-tune the mount
behavior, however. We can customize the
nsmb.conf file to use
different user names to access different shares, or to bypass NetBIOS
name resolution for particular hosts. Here's a more complicated
example, with comments.
[default] workgroup=EXAMPLE nbns=192.168.2.80 username=mlucas #I have a share on my desktop with a separate password [desktop:mlucas] password=$$1725a5038393e12ee #development is in a different NT domain, with #a shared username [development] workgroup=EXAMPLE2 username=support
Ownership of files across these systems can be problematic. Your Unix
user names probably don't map to Windows user names, and Unix has a
different permissions scheme. Because you're using a single Windows
user name to access the share, you have whatever access that account
has to the Windows resources. You should assign the proper Unix
permissions for that share, however. By default,
the new share the same permissions as the mount point used. The
/home/mwlucas/smbmount in our example is owned by "mwlucas",
in the group "mwlucas", and has mode 755. I can edit what's in this
directory, but no other users can. You can use
option to choose a different mode, and the
-d option to choose a
different directory mode. For example, to set it so only I could
access the contents of this directory I would use
mount_smbfs -d 700.
(This would make the Unix permissions far more stringent than the
Windows ones, but that's not my concern at the moment.) I can even
change the owner with the
-u option, and the group with the
-I option tells
mount_smbfs to skip NetBIOS name resolution, and
instead use the host name or IP address provided on the command line.
-N means that
mount_smbfs should read the password from the
configuration file, and not prompt for a password. This means that
you need to have your clear-text password in
-Wflag specifies a new workgroup. It overrides any settings in
Windows is case-insensitive; Unix is case-sensitive. SMBFS defaults
to leaving the case as it finds it, but this is not necessarily what
you want. The
-c flag tells
mount_smbfs to change the case.
-c l changes everything to lowercase, while
-c u changes everything to uppercase.
In working with
mount_smbfs, I've found it flexible enough to handle almost any situation on a Windows network. This allows you to use
your FreeBSD system seamlessly with the rest of the office.
Michael W. Lucas
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