Difference between revisions of "Setting up Samba as a Print Server"

(Moved "Granting the SePrintOperatorPrivilege Privilege" section from page "Setting up Samba as a Print Server" to page "Setting up Automatic Printer Driver Downloads for Windows Clients". It's only required for the driver stuff, so it fits better there.)
(Fixed incorrect location of the "printing" parameter. It must be set in [global], not in [printers].)
 
(One intermediate revision by the same user not shown)
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= Enabling the <code>spoolssd</code> Daemon =
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= Enabling the <code>spoolssd</code> Service =
  
''Optional''. On a Samba print server that processes a high number of print jobs, you can enable the <code>spoolssd</code> daemon to increase the Samba performance. Without <code>spoolssd</code>, Samba forks the <code>smbd</code> process for each print job and initializes the printcap cache. In case of a large number of printers, the <code>smbd</code> process can become unresponsive for multiple seconds when initializing the printcap cache. The <code>spoolssd</code> daemon enables you to start pre-forked <code>smbd</code> processes that are processing print jobs without delay. The main <code>spoolssd</code> <code>smbd</code> process uses a low amount of memory, and forks and terminates child processes.
+
The Samba <code>spoolssd</code> is a service that is integrated into the smbd service. If you configured Samba as a print server, you can additionally enable <code>spoolssd</code> to:
 +
* Support package-aware Windows drivers.
 +
* Increase performance on print servers with a high number of jobs or printers.
 +
: Without <code>spoolssd</code>, Samba forks the <code>smbd</code> process or each print job and initializes the <code>printcap</code> cache. In case of a large number of printers, the <code>smbd</code> service can become unresponsive for multiple seconds when initializing the cache. The <code>spoolssd</code> service enables you to start pre-forked <code>smbd</code> processes that are processing print jobs without any delay. The main <code>spoolssd</code> <code>smbd</code> process uses a low amount of memory, and forks and terminates child processes
  
To enable <code>spoolssd</code>:
+
To enable the <code>spoolssd</code> service:
  
* Add the following parameters to the <code>[global]</code> section of your <code>smb.conf</code> file:
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* Edit the <code>[global]</code> section in your <code>smb.conf</code> file:
 +
 
 +
:* Add the following parameters:
  
 
  rpc_server:spoolss = external
 
  rpc_server:spoolss = external
 
  rpc_daemon:spoolssd = fork
 
  rpc_daemon:spoolssd = fork
  
* Optionally, you can set the following parameters to fine-tune <code>spoolssd</code>
+
:* Optionally, you can set the following parameters:
spoolssd:prefork_min_children = 5           # Minimum number of child processes
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::{| class="wikitable"
spoolssd:prefork_max_children = 25         # Maximum number of child processes
+
!Parameter
spoolssd:prefork_spawn_rate = 5             # Fork this number of new child processes, up to the value set in the <code>spoolssd:prefork_max_children</code> parameter,
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!Default
                                            # if a new connection is established
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!Description
spoolssd:prefork_max_allowed_clients = 100 # Number of clients, a child process is responsible for
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|-
spoolssd:prefork_child_min_life = 60       # Minimum lifetime of a child process (60 seconds minimum)
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|spoolssd:prefork_min_children
 
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|5
: The values used in the previous example are the defaults.
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|Minimum number of child processes
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|-
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|spoolssd:prefork_max_children
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|25
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|Maximum number of child processes
 +
|-
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|spoolssd:prefork_spawn_rate
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|5
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|Samba forks this number of new child processes, up to the value set in <code>spoolssd:prefork_max_children</code>, if a new connection is established
 +
|-
 +
|spoolssd:prefork_max_allowed_clients
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|100
 +
|Number of clients, a child process serves
 +
|-
 +
|spoolssd:prefork_child_min_life
 +
|60
 +
|Minimum lifetime of a child process in seconds. 60 seconds is the minimum.
 +
|}
  
 
* Restart Samba.
 
* Restart Samba.
  
After the restart, Samba automatically forks additional <code>smbd</code> processes. To verify, enter:
+
After the restart, Samba automatically starts <code>smbd</code> sub-processes:  
 
  # ps axf
 
  # ps axf
 
  ...
 
  ...
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To enable the print server support:
 
To enable the print server support:
  
* Add the following section to your <code>smb.conf</code> file:
+
* Set the printing back end in the <code>printing</code> parameter of the <code>[global]</code> section in your <code>smb.conf</code> file. For example:
 +
printing = CUPS
 +
 
 +
* Add the following section to your <code>smb.conf</code>:
  
 
  [printers]
 
  [printers]
 
         path = /var/spool/samba/
 
         path = /var/spool/samba/
 
         printable = yes
 
         printable = yes
        printing = ''print_server_back_end''
 
 
:In the <code>printing</code> parameter, set the print server back end, such as <code>CUPS</code>.
 
  
 
* Create the spool directory set in the <code>path</code> parameter:
 
* Create the spool directory set in the <code>path</code> parameter:

Latest revision as of 12:03, 18 October 2017

Introduction

If you set up Samba as a print server, clients in your network are able to send print jobs to the Samba host using the server message block (SMB) protocol. The examples shown in this documentation use a raw printer in the back end. This configuration requires that the print job is formatted by a driver on the client and thus can be processed by the printer without further processing or filtering.



Supported Print Server Back Ends

Samba supports the multiple print server back ends, such as CUPS and LPRng. For a complete list, see the printing parameter in the smb.conf(5) man page.

For details how to set up the back end, see the print server's documentation.


Samba CUPS or IPRINT Back End Support

When using the CUPS or IPRINT print server back end, Samba must have been built with CUPS support enabled. To verify, enter:

# smbd -b | grep "HAVE_CUPS"
   HAVE_CUPS

If no output is displayed:



Adding a printer to the Print Server Back End

CUPS

To add a raw printer to an CUPS print server:

  • Open the CUPS admin web interface in your browser. For example, https://servername:631/admin
  • Select the Administration tab and click Add Printer.
  • Select the connection type and enter the corresponding URL to the printer's queue or to the remote print server queue. For example:
  • LPD-based printers: lpd://printer_name/queue
  • IPP (Internet Printing Protocol)-based printers: ipp://printer_name/ipp/port
  • SMB (Server Message Block)-based printers: smb://username:password@domain/windows_print_server_host_name/printer_name
Note that forwarding a job to a print server running Windows Vista or newer, or Windows Server 2008 or newer requires authentication.
  • Enter a name for the printer. This name is used in the smb.conf when sharing the printer using Samba.
  • Select the Raw printer vendor and model.
  • Save the settings.


LPRng

To add a raw printer to a LPRng print server:

  • Add the following line to the /etc/printcap file:
printer_name:sd=/var/spool/lpd/printer_name/:sh:mx=0:mc=0:rm=Printer_DNS_name_or_IP_address
The printer name is used in the smb.conf when sharing the printer using Samba.
For further details about the options used, see the printcap(5) man page.
  • To create the spool directory, enter:
# checkpc -f
  • Restart the LPRng service.



Enabling the spoolssd Service

The Samba spoolssd is a service that is integrated into the smbd service. If you configured Samba as a print server, you can additionally enable spoolssd to:

  • Support package-aware Windows drivers.
  • Increase performance on print servers with a high number of jobs or printers.
Without spoolssd, Samba forks the smbd process or each print job and initializes the printcap cache. In case of a large number of printers, the smbd service can become unresponsive for multiple seconds when initializing the cache. The spoolssd service enables you to start pre-forked smbd processes that are processing print jobs without any delay. The main spoolssd smbd process uses a low amount of memory, and forks and terminates child processes

To enable the spoolssd service:

  • Edit the [global] section in your smb.conf file:
  • Add the following parameters:
rpc_server:spoolss = external
rpc_daemon:spoolssd = fork
  • Optionally, you can set the following parameters:
Parameter Default Description
spoolssd:prefork_min_children 5 Minimum number of child processes
spoolssd:prefork_max_children 25 Maximum number of child processes
spoolssd:prefork_spawn_rate 5 Samba forks this number of new child processes, up to the value set in spoolssd:prefork_max_children, if a new connection is established
spoolssd:prefork_max_allowed_clients 100 Number of clients, a child process serves
spoolssd:prefork_child_min_life 60 Minimum lifetime of a child process in seconds. 60 seconds is the minimum.
  • Restart Samba.

After the restart, Samba automatically starts smbd sub-processes:

# ps axf
...
30903 smbd
30912  \_ smbd
30913      \_ smbd
30914      \_ smbd
30915      \_ smbd
...



Enabling the Print Server Support in Samba

To enable the print server support:

  • Set the printing back end in the printing parameter of the [global] section in your smb.conf file. For example:
printing = CUPS
  • Add the following section to your smb.conf:
[printers]
       path = /var/spool/samba/
       printable = yes
  • Create the spool directory set in the path parameter:
# mkdir -p /var/spool/samba/
# chmod 1777 /var/spool/samba/
  • Reload Samba:
# smbcontrol all reload-config



Sharing a Printer

Automatic Sharing of All Printers Configured in the Print Server Back End

Using the default setting, all printers configured in the print server back end are automatically shared.


Disabling the Automatic Printer Sharing

To disable the automatic printer sharing:

  • Add the following parameter to the [global] section of your smb.conf file:
load printers = no
  • Reload Samba:
# smbcontrol all reload-config


Manual Sharing of Printers

To manually share a printer:

  • Add the share for the printer to your smb.conf file:
[Samba_printer_name]
       path = /var/spool/samba/
       printable = yes
       printer name = printer_name_in_the_back_end
Set the printer name parameter to the name of the printer used in the local print server back end.
  • Reload Samba:
# smbcontrol all reload-config



Setting up Automatic Printer Driver Download for Windows Clients

See Setting up Automatic Printer Driver Downloads for Windows Clients.