Stable SMB
Pages: 1, 2

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] section.

[default]
workgroup=EXAMPLE
nbns=192.168.2.80
username=mlucas

With this information, you should be able to perform basic SMB name queries. 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 functions.

# 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 with mount_smbfs(8). The syntax is very simple.

mount_smbfs //username@servername/share /mount/point

To mount my personal fileserver share on /home/mwlucas/smbmount, I would do:

# mount_smbfs //mlucas@fileserv4/mlucas /home/mwlucas/smbmount

Check your work with df(1).

#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 better. 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, mount_smbfs assigns the new share the same permissions as the mount point used. The directory /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 mount_smbfs's -f 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 -g option.

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 nsmb.conf.

The -W flag specifies a new workgroup. It overrides any settings in nsmb.conf.

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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