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Chapter 10. Printing

This chapter tackles the topic of setting up printers for use with Samba. Aside from the "coolness factor" of seeing documents from Windows word processing and graphics applications appearing in the output tray of the Unix printer, this facility can greatly increase the usefulness of your Samba server. In many organizations, using a Unix system as the print server has led to happier system administrators and users alike, due to the reduced frequency of problems.

Samba allows client machines to share printers connected to the Samba host system, and Samba can also send Unix documents to printers shared by Windows systems. In this chapter, we discuss how to get printers configured to work in either direction.

We focus in this chapter on getting Samba to serve up printers that are already functioning on the Unix host. We include just a few basics about setting up printers on Unix. Good references for this topic include Network Printing, Essential System Administration, and Running Linux, all by O'Reilly and Associates.

Sending Print Jobs to Samba

A printer shared by the Samba server shows up in the list of shares offered in the Network Neighborhood. If the printer is registered on the client machine and the client has the correct printer driver installed, the client can effortlessly send print jobs to a printer attached to a Samba server. Figure 10-1 shows a Samba printer as it appears in the Network Neighborhood of a Windows client.

Figure 10-1. A Samba printer in the Network Neighborhood

To administer printers with Samba, you should understand the basic process by which printing takes place on a network. On the client system, the application software prints by utilizing the system's printer driver for the printer that will be creating the actual output. It is the printer driver software running on the client system that translates the application's high-level calls into a stream of binary data specific to the model of printer in use. In the case of a serial, parallel, or USB printer, the data is stored in a temporary file in the local system's printer queue and then sent through the respective port directly to the printer. For a network printer, the file is sent over the network.


Because the data has already been processed through a printer driver by the time it reaches the Samba host, make sure the printer on the Unix system is configured without any printer driver and that it will print whatever data it receives in raw form. If you already have the printer configured for use by Unix applications, you might need to set up another queue for it to print documents received from Windows clients correctly.

Sending a print job to a printer on a Samba server involves four steps:

  1. Opening and authenticating a connection to the printer share

  2. Copying the file over the network

  3. Closing the connection

  4. Printing and deleting the copy of the file

When a print job arrives at a Samba server, the print data is temporarily written to disk in the directory specified by the path option of the printer share. Samba then executes a Unix print command to send that datafile to the printer. The job is then printed as the authenticated user of the share. Note that this can be the guest user, depending on how the share is configured.

A Minimal Printing Setup

Let's start with a simple yet illustrative printing share. Assuming that you're on a Linux system and you have a printer called netprinter listed in the printer capabilities file, the following addition to your smb.conf file makes the printer accessible through the network:

    printable = yes
    print command = /usr/bin/lpr -P%p -r %s
    printer = netprinter
    printing = BSD
    path = /var/tmp

The variable %s in the print command option is replaced with the name of the file to be printed when Samba executes the command. There are four Samba configuration-file variables specifically for use with printing options. They are shown in Table 10-1.

Table 10-1. Printing variables




The full pathname of the file on the Samba server to be printed


The name of the file itself (without the preceding path) on the Samba server to be printed


The name of the Unix printer to use


The number of the print job (for use with lprm, lppause, and lpresume)

For other flavors of Unix, it is necessary to modify both the printing and print command options. For System V Unix, we would specify:

    printing = SYSV
    print command = lp -d%p -s %s; rm %s

With the printing = SYSV parameter, we notify Samba that the local printing system uses the System V Unix method. As mentioned earlier, the %p variable resolves to the name of the printer, while the %s variable resolves to the name of the file.

Clients might need to request the status of a print job sent to the Samba server. Because Samba sends print jobs to the Unix printing system for spooling, there might be a number of jobs in the queue at any given time. Consequently, Samba needs to communicate to the client not only the status of the current printing job, but also which documents are waiting to be printed on that printer. Samba also has to provide the client the ability to pause print jobs, resume print jobs, and remove print jobs from the printing queue. Samba provides options for each of these tasks. As you might expect, they borrow functionality from the following existing Unix commands:

We cover these options in more detail later in this chapter. For the most part, Samba provides reasonable default values for them based on the value of the printing configuration option, so you can probably get by without having to formulate your own commands for them.

Here are a few important items to remember about printing shares:

Using one or more Samba machines as a print server gives you a great deal of flexibility on your LAN. You can easily partition your available printers, restricting some to members of one department, or you can maintain a bank of printers available to all. In addition, you can restrict a printer to a select few by adding the valid users option to its share definition:

    printable = yes
    path = /var/spool/samba/print
    valid users = elizabeth cozy jack heather alexander lina emerald

All the other share accessibility options work for printing shares as well.

The [printers] Share

If a share named [printers] is in the configuration file, Samba will automatically read in your printer capabilities file and create a printing share for each printer that appears in the file. For example, if the Samba server had lp, pcl, and ps printers in its printer capabilities file, Samba would provide three printer shares with those names, each configured with the options in the [printers] share.

Recall that Samba obeys the following rules when a client requests a share that has not been created with an explicit share definition in the smb.conf file:

This brings to light an important point: be careful that you do not give a printer the same name as a user. Otherwise, users end up connecting to a disk share when they might have wanted a printer share instead.

Here is an example [printers] share for a Linux system. Some of these options are already defaults; however, we have listed them anyway for illustrative purposes:

    printable = yes
    printing = BSD
    printcap name = /etc/printcap
    print command = /usr/bin/lpr -P%p -r %s
    path = /var/spool/lpd/tmp
    min print space = 2000

Here, we've given Samba global options that specify the printing type (BSD), a print command to send data to the printer and later remove the temporary file, the location of our printer capabilities file, and a minimum disk space for printing of 2MB.

In addition, we've created a [printers] share for each system printer. Our temporary spooling directory is specified by the path option: /var/spool/lpd/tmp. Each share is marked as printable—this is a necessary option, even in the [printers] section.

Testing the Configuration

After running testparm and restarting the Samba daemons, you can check to make sure everything is set up correctly by using smbclient to send a file to the printer. Connect to the printer using the command:

# smbclient /server/printshare

and then use the print command to print a file:

smb: /> print textfile


If you connect to a print share served by a Windows 95/98/Me system configured to use user-mode security and cannot authenticate using what you know to be a correct username and password, try reconfiguring the Windows system to use share-mode security.

When you print something through the Samba server via smbclient, the following actions should occur:

If smbclient cannot print, you can reset the print command option to collect debugging information:

print command = echo "printed %s on %p" >>/tmp/printlog

A common problem with Samba printer configuration is forgetting to use the full pathnames for commands. Another frequent problem is not having the correct permissions on the spooling directory.[1] As usual, check your Samba log files and system log files for error messages. If you use BSD printing, you can change the lp keyword in the printer's printcap entry to something other than /dev/null, allowing you to collect error messages from the printing system.


More information on debugging printers is in the file docs/textdocs/Printing.txt in the Samba source distribution. The Unix print systems are covered in detail in фleen Frisch's Essential Systems Administration (published by O'Reilly).

Setting Up and Testing a Windows Client

Now that Samba is offering a workable printer, you can set up your access to it on a Windows client. Browse through the Samba server in the Network Neighborhood. It should now show each printer that is available. For example, in Figure 10-1, we saw a printer called lp.

Next, you need to have the Windows client recognize the printer. Double-click the printer icon to get started. If you try to select an uninstalled printer (as you just did), Windows will ask you if it should help configure it for the Windows system. Click the Yes or OK button, and the Printer Wizard will open.

If you are installing a printer on Windows 95/98/Me, the first thing the wizard will ask is whether you need to print from DOS. Let's assume you don't, so choose the "No" radio button and press the Next > button to get to the manufacturer/model window, as shown in Figure 10-2.

Figure 10-2. Setting the manufacturer and model of the printer

In this dialog box, you should see a large list of manufacturers and models for a huge number of printers. Select the manufacturer of your printer in the left side of the dialog box, and then the exact model of the printer in the list on the right side.

In some cases, you might not find your printer in the list, or the version of the printer driver included with Windows might be out of date. In cases such as these, consult the printer manufacturer's documentation on how to install the driver. Typically, you will click the Have Disk... button to install the driver from a CD-ROM or disk file.

If you don't see your printer on the list, but you know it's a PostScript printer, select Apple as the manufacturer and Apple LaserWriter as the model. This will give you the most basic PostScript printer setup—and arguably one of the most reliable. If you already have PostScript printers attached, you will be asked about replacing or reusing the existing driver. Be aware that if you replace it with a new one, you might make your other printers fail. Therefore, we recommend you keep using your existing printer drivers as long as they're working properly.

Click the Next > or OK button. On Windows 95/98/Me, the Printer Wizard asks you to name the printer. On Windows NT/2000/XP, you need to right-click the printer's icon and select Properties to assign the printer a name. Figure 10-3 shows how we've named our printer to show that it's shared by the mixtec Samba server.

Figure 10-3. Setting the printer name

Finally, on Windows 95/98/Me the Printing Wizard asks if it should print a test page. Click the "Yes" radio button, then the Finish button, and you should be presented with the dialog box shown in Figure 10-4. On Windows NT/2000/XP, the printer test function is also accessed through the printer's Properties dialog box.

Figure 10-4. Sending a test page to the printer

If the test printing was unsuccessful, click the No button and the Printing Wizard will walk you through some debugging steps for the client side of the process. If the test printing does work, the remote printer will now be available to all Windows applications through the File and Print menu items.

Printing to Windows Printers

If you have printers connected to systems running Windows 95/98/Me or Windows NT/2000/XP, the printers can also be accessed from your Unix system using tools that are part of the Samba distribution. First, it is necessary to create a printer share on the Windows system. Then set up the printer on the Unix side by configuring a new printer and using a Samba printing program as the printer's filter.

Adding a Unix Printer

The Samba distribution comes with three programs that assist with printing on shared printers. The smbprint program works with systems that use the BSD printing system, smbprint.sysv works with systems that use System V printing, and smbspool works with systems that use the Common Unix Printing System (CUPS). In the following sections we show you how to install printers for each system.

BSD printers

The BSD printing system is used by many Unix variants, including Red Hat Linux. With BSD printing, all the printers on the system have an entry in the /etc/printcap file, which is the database of printer capabilities used by the lpd line printer daemon and other programs that assist with printing. The Red Hat Linux implementation is a bit different in that /etc/printcap is a machine-generated file, which is re-created every time the lpd daemon is restarted by the /etc/rc.d/init.d/lpd script. Instead of editing /etc/printcap, we will add an entry for our printer in /etc/printcap.local, which the system automatically includes verbatim when creating /etc/printcap.


If you are using the version of Samba installed from an RPM file as on Red Hat Linux, you might be able to skip these directions and use the printconf tool, which has support for SMB printers. Unfortunately, this tool might not work correctly if you have installed Samba from the Samba source distribution.

Here is the entry we added to our /etc/printcap.local file to support our Hewlett-Packard DeskJet 932C printer, which is shared by maya, a Windows 98 system:

    :cm=HP 932C on maya:\

The first line creates names for the printer. We are calling it both maya-hp932c, to describe its location on the network and the type of printer, and lp so that programs will use it as the default printer. The rest of the lines specify keywords and values. The cm keyword allows us to assign a comment string to the printer. The sd and af keywords assign the printer's spool directory and accounting files, respectively. The if keyword assigns the print filter. We are using the smbprint command to send the output to the shared SMB printer. The mx keyword is set to zero to allow any size file to be printed, and lp is set to /dev/null to discard error messages.

You can follow our model to create an entry for your own printer. If you want to go beyond the capabilities we used, refer to your system's printcap(5) manual page for a complete listing of keywords.

Go to your Samba source distribution's root directory, and install the smbprint program like this:

# cp examples/printing/smbprint /usr/local/samba/bin

We next create the printer's spool directory:

# cd /var/spool/lpd
# mkdir maya
# chown lp:lp maya
# chmod 700 maya

The smbprint program looks for a file named .config in the printer's spool directory, which contains information on how to connect to the printer share. We create this file and then fill in the required information:

# cd maya
# >.config
# chown lp:lp .config
# chmod 600 .config

Use your preferred text editor to edit the .config file, and enter three lines, like this:


This is for our shared printer having a UNC of \\maya\hp. When we created the printer share, we did not give it a password, so we use a null password here. If your printer share is on a Windows NT/2000/XP system, use your domain password.

Finally, restart the printer daemon:

# /etc/rc.d/init.d/lpd restart

You can now try printing something. Run the following command:

$ lpr textfile

If you have everything set up correctly, the file prints on the shared printer. If you get "stair stepping" of text, caused by the printer not returning to the left margin at the beginning of every line, modify the if keyword in your printcap entry to run smbprint with the -t option.

CUPS printers

CUPS[2] uses a set of modules, called backends, to send print jobs to various destinations, such as local printers attached to parallel, serial, or Universal Serial Bus (USB) ports, or over the network using Unix line printer daemon (LPD) protocol, Internet Printing Protocol (IPP), AppleTalk Printer Access Protocol (PAP), and so on. The software package does not come with a backend for SMB; the Samba suite includes the smbspool utility for this purpose.

To enable printing to remote SMB printers using CUPS, create a symbolic link named smb in the CUPS backend directory pointing to smbspool. Depending on installation options, these could be in a number of places in the directory hierarchy, so be sure to check your system. Using a common default installation, the command would look like this:

# ln -s /usr/local/samba/bin/smbspool /usr/lib/cups/backend/smb

Issue a HUP signal to the CUPS daemon, cupsd, and check for the existence of SMB support with the lpinfo -v command. Its output should now include a line that says network smb.

To add a printer, use the CUPS web interface, accessible on the local system at http://localhost:631/, or use the lpadmin command:

# lpadmin -p hp932c -E -v smb://maya/hp932c -D "HP 932C on maya"

This creates and enables the new print spool called hp932c. The -v argument specifies the printer device, which in this case is accessed over the network using an SMB URI. If the printer is not guest-accessible, you'll need to provide a username and password in the URI. The full format is as follows:


The lpadmin command makes changes to /etc/cups/printers.conf and sends a HUP signal to the cupsd daemon, resulting in the creation of a local raw printer spool. In this example, print data is passed in raw format to the Windows system, which has the necessary printer drivers and printer description files to format the data appropriately. The -D option is used to give the printer a comment string.

Once you have the printer set up, it's time to test it out. CUPS understands both BSD-style and System V-style printing commands, so you can use whichever is more comfortable. Using the BSD lpr command, try something like:

$ lpr -P hp932c textfile

You should now be set up to use the printer from any application on the Unix system.

Samba Printing Options

Table 10-2 summarizes the Samba printing options.

Table 10-2. Printing configuration options







bsd, sysv, cups, hpux, aix, qnx, plp, softq, or lprng

Printing system type of the Samba host



printable (print ok)


Marks a share as a printing share



printer (printer name)

string (Unix printer name)

Name for the printer that is shown to clients



lpq cache time

numeric (time in seconds)

Amount of time in seconds that Samba will cache the printer queue status





Treats all print jobs as PostScript by prefixing %! at the beginning of each file



load printers


If yes, automatically loads each printer in the printcap file as printing shares



print command

string (shell command)

Unix command to perform printing

See below


lpq command

string (shell command)

Unix command to return the status of the printing queue

See below


lprm command

string (shell command)

Unix command to remove a job from the printing queue

See below


lppause command

string (shell command)

Unix command to pause a job on the printing queue

See below


lpresume command

string (shell command)

Unix command to resume a paused job on the printing queue

See below


printcap name


string (filename)

Location of the printer capabilities file



min print space

numeric (size in kilobytes)

Minimum amount of free disk space that must be present to print



queuepause command

string (shell command)

Unix command to pause a queue

See below


queueresume command

string (shell command)

Unix command to resume a queue

See below



The printing configuration option tells Samba which printing system to use. There are several different families of commands to control printing and print statusing. Samba supports seven different types, as shown in Table 10-3.

Table 10-3. Printing system types




Berkeley Unix system


System V


Common Unix Printing System


IBM's AIX operating system


Hewlett-Packard Unix


QNX Realtime Operating System


LPR Next Generation


SOFTQ system


Portable Line Printer

The value for this option must be one of these seven selections. For example:

printing = SYSV

The default value of this option is system-dependent and is configured when Samba is first compiled. For most systems, the configure script automatically detects the printing system to be used and configures it properly in the Samba makefile. However, if your system is a PLP, LPRNG, or QNX printing system, you need to specify this explicitly in the makefile or the printing share.

The most common system types are BSD, SYSV, and CUPS. Each printer on a BSD Unix server is described in the printer capabilities file—normally /etc/printcap. See the section on the printcap file parameter for more information on this topic.

Setting the printing configuration option automatically sets at least three other printing options for the service in question: print command, lpq command, and lprm command. If you are running Samba on a system that doesn't support any of the printing styles listed in Table 10-3, simply set the commands for each of these manually.

load printers

The load printers option tells Samba to create shares for all known printer names and load those shares into the browse list. Samba will create and list a printer share for each printer name in /etc/printcap (or the system equivalent). For example, if your printcap file looks like this:[3]

  :sd=/var/spool/lpd/lp:\            spool directory
  :mx#0:\                            maximum file size (none)
  :sh:\                              supress burst header (no)
  :lp=/dev/lp1:\                     device name for output
  :if=/var/spool/lpd/lp/filter:      text filter

  :sd=/var/spool/lpd/laser:\         spool directory
  :mx#0:\                            maximum file size (none)
  :sh:\                              supress burst header (no)
  :lp=/dev/laser:\                   device name for output
  :if=/var/spool/lpd/lp/filter:      text filter

the shares [lp] and [laser] are automatically created as valid print shares when Samba is started. Both shares borrow the configuration options specified in the [printers] section to configure themselves and are available in the browse list for the Samba server. The default value for this option is yes. If you prefer to specify each printer explicitly in your configuration file, use the following:

    load printers = no

print command, lpq command, lprm command,lppause command, lpresume command

These options tell Samba which Unix commands control and send data to the printer. The Unix commands involved are: lpr (send to Line PRinter), lpq (List Printer Queue), lprm (Line Printer ReMove), and optionally lppause and lpresume. Samba provides an option named after each command, in case you need to override any of the system defaults. For example, consider the following:

lpq command = /usr/ucb/lpq %p

This would set lpq command to use /usr/ucb/lpq. Similarly:

lprm command = /usr/local/bin/lprm -P%p %j

would set the Samba printer remove command to /usr/local/bin/lprm and provide it the print job number using the %j variable.

The default values for each option are dependent on the value of the printing option. Table 10-4 shows the default commands for each printing option. The most popular printing system is BSD.

Table 10-4. Default commands for various printing options






print command

lpr -r -P%p %s

lp -c -d%p %s; rm %s

lp -r -P%p %s

lp -d%p -s %s; rm %s

lpq command

lpq -P%p

lpstat -o%p

lpq -P%p

lpstat -o%p

lprm command

lprm -P%p %j

cancel %p-%j

cancel %p-%j

cancel %p-%j

lppause command

lp -i %p-%j -H hold

(SYSV only)




lpresume command

lp -i %p-%j -H resume

(SYSV only)



qstat -s -j%j -r

It is usually unnecessary to reset these options in Samba, with the possible exception of the print command. This option might need to be set explicitly if your printing system doesn't have a -r (remove after printing) option on the printing command. For example:

print command = /usr/local/lpr -P%p %s; /bin/rm %s

With a bit of judicious programming, these smb.conf options can also be used for debugging:

print command = cat %s >>/tmp/printlog; lpr -r -P%p %s

Using the previous configuration, it is possible to verify that files are actually being delivered to the Samba server. If they are, their contents will show up in the file /tmp/printlog.

After BSD, the next most popular kind of printing system is SYSV (or System V) printing, plus some SYSV variants for IBM's AIX and Hewlett-Packard's HP-UX. These systems do not have an /etc/printcap file. Instead, the printcap file option can be set to an appropriate lpstat command for the system. This tells Samba to get a list of printers from the lpstat command. Alternatively, you can set the global configuration option printcap name to the name of a dummy printcap file you provide. In the latter case, the file must contain a series of lines such as:

lp|print1|My Printer 1
print2|My Printer 2
print3|My Printer 3

Each line names a printer followed by aliases for it. In this example, the first printer is called lp, print1, or My Printer 1, whichever the user prefers to use. The first name is used in place of %p in any command Samba executes for that printer.

Two additional printer types are also supported by Samba: LPRNG (LPR New Generation) and PLP (Public Line Printer). These are public domain and open source printing systems and are used by many sites to overcome problems with vendor-supplied software. Samba also supports the printing systems of the SOFTQ and QNX real-time operating systems.


[1] If you are using Linux, you can use the checkpc command to check for this type of error.

[2] CUPS is open source software (http://www.opensource.org) developed by Easy Software Products. For more information, visit http://www.cups.org.

[3] We have placed annotated comments off to the right in case you've never dealt with this file before.