cups-browsed.conf

cups-browsed.conf(5) cups-browsed.conf(5)

NAME

   cups-browsed.conf - server configuration file for cups-browsed

DESCRIPTION

   The cups-browsed.conf file configures the cups-browsed daemon. It is normally located in the /etc/cups directory. Each line in the file can be a configuration directive, a blank line,
   or a comment. Comment lines start with the # character.

DIRECTIVES

   The "CacheDir" directive determines where cups-browsed should save information about the print queues it had generated when shutting down, like whether one of these queues was the de
   fault printer, or default option settings of the queues.

           CacheDir /var/cache/cups

   With "LogDir" can be defined where cups-browsed creates its debug log file (if "DebugLogging file" is set).

           LogDir /var/log/cups

   The "DebugLogging" directive determines how should debug logging be done.  Into the file /var/log/cups/cups-browsed_log ("file"), to stderr ("stderr"), or not at all ("none").

   Note  that if cups-browsed is running as a system service (for example via systemd) logging to stderr makes the log output going to the journal or syslog. Only if you run cups-browsed
   from the command line (for development or debugging) it will actually appear on stderr.

           DebugLogging file
           DebugLogging stderr
           DebugLogging file stderr
           DebugLogging none

   Only browse remote printers (via DNS-SD or CUPS browsing) from selected servers using the "BrowseAllow", "BrowseDeny", and "BrowseOrder" directives

   This serves for restricting the choice of printers in print dialogs to trusted servers or to reduce the number of listed printers in the print dialogs to a more  user-friendly  amount
   in large networks with very many shared printers.

   This only filters the selection of remote printers for which cups-browsed creates local queues. If the print dialog uses other mechanisms to list remote printers as for example direct
   DNS-SD access, cups-browsed has no influence. cups-browsed also does not prevent the user from manually accessing non-listed printers.

   "BrowseAllow":  Accept  printers  from these hosts or networks. If there are only "BrowseAllow" lines and no "BrowseOrder" and/or "BrowseDeny" lines, only servers matching at last one
   "BrowseAllow" line are accepted.

   "BrowseDeny": Deny printers from these hosts or networks. If there are only "BrowseDeny" lines and no "BrowseOrder" and/or "BrowseAllow" lines, all servers NOT  matching  any  of  the
   "BrowseDeny" lines are accepted.

   "BrowseOrder":  Determine  the  order  in  which  "BrowseAllow"  and  "BrowseDeny" lines are applied. With "BrowseOrder Deny,Allow" in the beginning all servers are accepted, then the
   "BrowseDeny" lines are applied to exclude unwished servers or networks and after that the "BrowseAllow" lines to re-include servers or networks. With "BrowseOrder Allow,Deny" we start
   with denying all servers, then applying the "BrowseAllow" lines and afterwards the "BrowseDeny" lines.

   Default for "BrowseOrder" is "Deny.Allow" if there are both "BrowseAllow" and "BrowseDeny" lines.

   If there are no "Browse..." lines at all, all servers are accepted.

           BrowseAllow All
           BrowseAllow 192.168.7.20
           BrowseAllow 192.168.7.0/24
           BrowseAllow 192.168.7.0/255.255.255.0

           BrowseDeny All
           BrowseDeny 192.168.1.13
           BrowseDeny 192.168.3.0/24
           BrowseDeny 192.168.3.0/255.255.255.0

           BrowseOrder Deny,Allow
           BrowseOrder Allow,Deny

   Filtering of remote printers by other properties than IP addresses of their servers

   Often the desired selection of printers cannot be reached by only taking into account the IP addresses of the servers. For these cases there is the BrowseFilter directive to filter by
   most of the known properties of the printer.

   By default there is no BrowseFilter line meaning that no filtering is applied.

   To do filtering one can supply one or more BrowseFilter directives like this:

           BrowseFilter [NOT] [EXACT] <FIELD> [<VALUE>]

   The BrowseFilter directive always starts with the word "BrowseFilter" and it must at least contain the name of the data field (<FIELD>) of the printer's properties to which it  should
   apply.

   Available field names are:

           name:    Name of the local print queue to be created
           host:    Host name of the remote print server
           port:    Port through which the printer is accessed on the server
           service: DNS/SD service name of the remote printer
           domain:  Domain of the remote print server

   Also  all  field  names  in  the  TXT  records  of DNS-SD-advertised printers are valid, like "color", "duplex", "pdl", ... If the field name of the filter rule does not exist for the
   printer, the rule is skipped.

   The optional <VALUE> field is either the exact value (when the option EXACT is supplied) or a regular expression (Run "man 7 regex" in a terminal window) to be matched with  the  data
   field.

   If no <VALUE> filed is supplied, rules with field names of the TXT record are considered for boolean matching (true/false) of boolean field (like duplex, which can have the values "T"
   for true and "F" for false).

   If  the  option  NOT  is  supplied,  the filter rule is fulfilled if the regular expression or the exact value DOES NOT match the content of the data field. In a boolean rule (without
   <VALUE>) the rule matches false.

   Regular expressions are always considered case-insensitive and extended POSIX regular expressions. Field names and options (NOT, EXACT) are all evaluated case-insensitive. If there is
   an error in a regular expression, the BrowseFilter line gets ignored.

   Especially to note is that supplying any simple string consisting of only letters, numbers, spaces, and some basic special characters as a regular expression matches  if  it  is  con‐
   tained somewhere in the data field.

   If there is more than one BrowseFilter directive, ALL the directives need to be fulfilled for the remote printer to be accepted. If one is not fulfilled, the printer will get ignored.

   Examples:

   Rules for standard data items which are supplied with any remote printer advertised via DNS-SD:

   Print queue name must contain "hum_res_", this matches "hum_res_mono" or "hum_res_color" but also "old_hum_res_mono":

           BrowseFilter name hum_res_

   This matches if the remote host name contains "printserver", like "printserver.local", "printserver2.example.com", "newprintserver":

           BrowseFilter host printserver

   This matches all ports with 631 int its number, for example 631, 8631, 10631,...:

           BrowseFilter port 631

   This rule matches if the DNS-SD service name contains "@ printserver":

           Browsefilter service @ printserver

   Matches all domains with "local" in their names, not only "local" but also things like "printlocally.com":

           BrowseFilter domain local

   Examples for rules applying to items of the TXT record:

   This  rule  selects PostScript printers, as the "PDL" field in the TXT record contains "postscript" then. This includes also remote CUPS queues which accept PostScript, independent of
   whether the physical printer behind the CUPS queue accepts PostScript or not.

           BrowseFilter pdl postscript

   Color printers usually contain a "Color" entry set to "T" (for true) in the TXT record. This rule selects them:

           BrowseFilter color

   This is a similar rule to select only duplex (automatic double-sided printing) printers:

           BrowseFilter duplex

   Rules with the NOT option:

   This rule EXCLUDES printers from all hosts containing "financial" in their names, nice to get rid of the 100s of printers of the financial department:

           BrowseFilter NOT host financial

   Get only monochrome printers ("Color" set to "F", meaning false, in the TXT record):

           BrowseFilter NOT color

   Rules with more advanced use of regular expressions:

   Only queue names which BEGIN WITH "hum_res_" are accepted now, so we still get "hum_res_mono" or "hum_res_color" but not "old_hum_res_mono" any more:

           BrowseFilter name ^hum_res_

   Server names is accepted if it contains "print_server" OR "graphics_dep_server":

           BrowseFilter host print_server|graphics_dep_server

   "printserver1", "printserver2", and "printserver3", nothing else:

           BrowseFilter host ^printserver[1-3]$

   Printers understanding at least one of PostScript, PCL, or PDF:

           BrowseFilter pdl postscript|pcl|pdf

   Examples for the EXACT option:

   Only printers from "printserver.local" are accepted:

           BrowseFilter EXACT host printserver.local

   Printers from all servers except "prinserver2.local" are accepted:

           BrowseFilter NOT EXACT host prinserver2.local

   The BrowsePoll directive polls a server for available printers once every 60 seconds. Multiple BrowsePoll directives can be specified to poll multiple servers.  The  default  port  to
   connect to is 631.  BrowsePoll works independently of whether CUPS browsing is activated in BrowseRemoteProtocols.

           BrowsePoll 192.168.7.20
           BrowsePoll 192.168.7.65:631
           BrowsePoll host.example.com:631

   The  BrowseLocalProtocols directive specifies the protocols to use when advertising local shared printers on the network. The default is "none". Control of advertising of local shared
   printers using dnssd is done in /etc/cups/cupsd.conf.

           BrowseLocalProtocols none
           BrowseLocalProtocols CUPS

   The BrowseRemoteProtocols directive specifies the protocols to use when finding remote shared printers on the network. Multiple protocols can be  specified  by  separating  them  with
   spaces.  The default is "dnssd cups".

           BrowseRemoteProtocols none
           BrowseRemoteProtocols CUPS dnssd
           BrowseRemoteProtocols CUPS
           BrowseRemoteProtocols dnssd
           BrowseRemoteProtocols ldap

   The  BrowseProtocols  directive specifies the protocols to use when finding remote shared printers on the network and advertising local shared printers. "dnssd" and "ldap" are ignored
   for BrowseLocalProtocols.  Multiple protocols can be specified by separating them with spaces. The default is "none" for BrowseLocalProtocols and "dnssd cups"  for  BrowseRemoteProto‐
   cols.

           BrowseProtocols none
           BrowseProtocols CUPS dnssd
           BrowseProtocols CUPS
           BrowseProtocols dnssd
           BrowseProtocols ldap

   The  configuration  for the LDAP browsing mode define where the LDAP search should be performed. If built with an LDAP library that supports TLS, the path to the server's certificate,
   or to a certificates store, can be specified.  The optional filter allows the LDAP search to be more specific, and is used  in  addition  to  the  hardcoded  filter  (objectclass=cup
   sPrinter).

           BrowseLDAPBindDN cn=cups-browsed,dc=domain,dc=tld
           BrowseLDAPCACertFile /path/to/server/certificate.pem
           BrowseLDAPDN ou=printers,dc=domain,dc=tld
           BrowseLDAPFilter (printerLocation=/Office 1/*)
           BrowseLDAPPassword s3cret
           BrowseLDAPServer ldaps://ldap.domain.tld

   The DomainSocket directive specifies the domain socket through which the locally running CUPS daemon is accessed. If not specified the standard domain socket of CUPS is used. Use this
   if  you  have  specified an alternative domain socket for CUPS via a Listen directive in /etc/cups/cupsd.conf. If cups-browsed is not able to access the local CUPS daemon via a domain
   socket it accesses it via localhost. "None" or "Off" lets cups-browsed not use CUPS' domain socket.

           DomainSocket /var/run/cups/cups.sock
           DomainSocket None
           DomainSocket Off

   Set HTTP timeout (in seconds) for requests sent to local/remote resources Note that too short timeouts can make services getting missed when they are present and operations be  unnec‐
   essarily repeated and too long timeouts can make operations take too long when the server does not respond.

           HttpLocalTimeout 5
           HttpRemoteTimeout 10

   Set  how many retries (N) should cups-browsed do for creating print queues for remote printers which receive timeouts during print queue creation.  The printers which are not success‐
   fully set up even after N retries, are skipped until the next restart of the service.  Note that too many retries can cause high CPU load.

           HttpMaxRetries 5

   The interval between browsing/broadcasting cycles, local and/or remote, can be adjusted with the BrowseInterval directive.

           BrowseInterval 60

   The BrowseTimeout directive determines the amount of time that browsing-related operations are allowed to take in seconds.  Notably, adding or removing one printer queue is considered
   as one operation. The timeout applies to each one of those operations.  Especially queues discovered by CUPS broadcasts will be removed after this timeout if no further broadcast from
   the server happens.

           BrowseTimeout 300

   The AllowResharingRemoteCUPSPrinters directive determines whether a print queue pointing to a remote CUPS queue will be re-shared to the local network or not. Since the queues  gener‐
   ated using the BrowsePoll directive are also pointing to remote queues, they are also shared automatically if the following option is set. Default is not to share remote queues.

           AllowResharingRemoteCUPSPrinters Yes

   The NewBrowsePollQueuesShared directive determines whether a print queue for a newly discovered printer (discovered by the BrowsePoll directive) will be shared to the local network or
   not. This directive will only work if AllowResharingRemoteCUPSPrinters is set to yes. Default is not to share printers discovered using BrowsePoll.

           NewBrowsePollQueuesShared Yes

   Set  OnlyUnsupportedByCUPS to "Yes" will make cups-browsed not create local queues for remote printers for which CUPS creates queues by itself.  These printers are printers advertised
   via DNS-SD and doing CUPS-supported (currently PWG Raster and Apple Raster) driverless printing, including remote CUPS queues.  Queues  for  other  printers  (like  for  legacy  Post‐
   Script/PCL printers) are always created (depending on the other configuration settings of cups-browsed).

   With  OnlyUnsupportedByCUPS  set  to  "No",  cups-browsed creates queues for all printers which it supports, including printers for which CUPS would create queues by itself. Temporary
   queues created by CUPS will get overwritten. This way it is assured that any extra functionality of cups-browsed will apply to these queues. As queues created by cups-browsed are per‐
   manent CUPS queues this setting is also recommended if applications/print dialogs which do not support temporary CUPS queues are installed. This setting is the default.

           OnlyUnsupportedByCUPS Yes

   With UseCUPSGeneratedPPDs set to "Yes" cups-browsed creates queues for IPP printers with PPDs generated by the PPD generator of CUPS and not with the one of cups-browsed. So  any  new
   development  in  CUPS'  PPD  generator  gets  available. As CUPS' PPD generator is not directly accessible, we need to make CUPS generate a temporary print queue with the desired PPD.
   Therefore we can only use these PPDs when our queue replaces a temporary CUPS queue, meaning that the queue is for a printer on which CUPS supports driverless printing (IPP 2.x, PDLs:
   PDF, PWG Raster, and/or Apple Raster) and that its name is the same as CUPS uses for the temporary queue ("LocalQueueNamingIPPPrinter DNS-SD" must be set). The directive applies  only
   to IPP printers, not to remote CUPS queues, to not break clustering. Setting this directive to "No" lets cups-browsed generate the PPD file. Default setting is "No".

           UseCUPSGeneratedPPDs No

   With  the directives LocalQueueNamingRemoteCUPS and LocalQueueNamingIPPPrinter you can determine how the names for local queues generated by cups-browsed are generated, separately for
   remote CUPS printers and IPP printers.

   "DNS-SD" (the default in both cases) bases the naming on the service name of the printer's advertised DNS-SD record. This is exactly the same naming scheme as CUPS uses for its tempo
   rary queues, so the local queue from cups-browsed prevents CUPS from listing and creating an additional queue. As DNS-SD service names have to be unique, queue names of printers  from
   different servers will also be unique and so there is no automatic clustering for load-balanced printing.

   "MakeModel" bases the queue name on the printer's manufacturer and model names. This scheme cups-browsed used formerly for IPP printers.

   "RemoteName" is only available for remote CUPS queues and uses the name of the queue on the remote CUPS server as the local queue's name. This makes printers on different CUPS servers
   with  equal queue names automatically forming a load-balancing cluster as CUPS did formerly (CUPS 1.5.x and older) with CUPS-broadcasted remote printers. This scheme cups-browsed used
   formerly for remote CUPS printers.

           LocalQueueNamingRemoteCUPS DNS-SD
           LocalQueueNamingRemoteCUPS MakeModel
           LocalQueueNamingRemoteCUPS RemoteName
           LocalQueueNamingIPPPrinter DNS-SD
           LocalQueueNamingIPPPrinter MakeModel

   Set DNSSDBasedDeviceURIs to "Yes" if cups-browsed should use DNS-SD-service-name-based device URIs for its local queues, as CUPS also does. These queues use the DNS-SD service name of
   the discovered printer. With this the URI is independent of network interfaces and ports, giving reliable connections to always the same physical device. This setting is the default.

   Set DNSSDBasedDeviceURIs to "No" if cups-browsed should use the conventional host-name/IP-based URIs.

   Note that this option has only influence on URIs for printers discovered via DNS-SD, not via legacy CUPS broewsing or LDAP.  Those printers get always assigned the conventional URIs.

           DNSSDBasedDeviceURIs Yes

   Set IPBasedDeviceURIs to "Yes" if cups-browsed should create its local queues with device URIs with the IP addresses instead of the host names of the  remote  servers.  This  mode  is
   there for any problems with host name resolution in the network, especially also if avahi-daemon is only run for printer discovery and already stopped while still printing. By default
   this mode is turned off, meaning that we use URIs with host names.

   Note  that the IP addresses depend on the network interface through which the printer is accessed. So do not use IP-based URIs on systems with many network interfaces and where inter
   faces can appear and disappear frequently.

   This mode could also be useful for development and debugging.

   If you prefer IPv4 or IPv6 IP addresses in the URIs, you can set IPBasedDeviceURIs to "IPv4" to only get IPv4 IP addresses or IPBasedDeviceURIs to "IPv6"  to  only  get  IPv6  IP  ad
   dresses.

           IPBasedDeviceURIs No
           IPBasedDeviceURIs Yes
           IPBasedDeviceURIs IPv4
           IPBasedDeviceURIs IPv6

   Set  CreateRemoteRawPrinterQueues  to  "Yes"  to  let  cups-browsed  also  create local queues pointing to remote raw CUPS queues. Normally, only queues pointing to remote queues with
   PPD/driver are created as we do not use drivers on the client side, but in some cases accessing a remote raw queue can make sense, for example if the queue forwards the jobs by a spe
   cial backend like Tea4CUPS.

           CreateRemoteRawPrinterQueues Yes

   cups-browsed by default creates local print queues for each shared CUPS print queue which it discovers on remote machines in the local network(s). Set CreateRemoteCUPSPrinterQueues to
   "No" if you do not want cups-browsed to do this. For example you can set cups-browsed to only create queues for IPP network printers setting CreateIPPPrinterQueues  not  to  "No"  and
   CreateRemoteCUPSPrinterQueues to "No".

           CreateRemoteCUPSPrinterQueues No

   Set  CreateIPPPrinterQueues to "All" to let cups-browsed discover IPP network printers (native printers, not CUPS queues) with known page description languages (PWG Raster, PDF, Post
   Script, PCL XL, PCL 5c/e) in the local network and auto-create print queues for them.

   Set CreateIPPPrinterQueues to "Everywhere" to let cups-browsed discover IPP Everywhere printers in the local network (native printers, not CUPS queues) and  auto-create  print  queues
   for them.

   Set CreateIPPPrinterQueues to "AppleRaster" to let cups-browsed discover Apple Raster printers in the local network (native printers, not CUPS queues) and auto-create print queues for
   them.

   Set  CreateIPPPrinterQueues  to "Driverless" to let cups-browsed discover printers designed for driverless use (currently IPP Everywhere and Apple Raster) in the local network (native
   printers, not CUPS queues) and auto-create print queues for them.

   Set CreateIPPPrinterQueues to "LocalOnly" to auto-create print queues only for local printers made available as IPP printers. These are for example IPP-over-USB printers, made  avail
   able via ippusbxd(8). This is the default.

   Set CreateIPPPrinterQueues to "No" to not auto-create print queues for IPP network printers.

   If queues with PPD file are created (see IPPPrinterQueueType directive below) the PPDs are auto-generated by cups-browsed based on properties of the printer polled via IPP. In case of
   missing information, info from the Bonjour record is used asd as last mean default values.

   If  queues  without PPD (see IPPPrinterQueueType directive below) are created clients have to IPP-poll the capabilities of the printer and send option settings as standard IPP attrib
   utes. Then we do not poll the capabilities by ourselves to not wake up the printer from power-saving mode when creating the queues. Jobs have to be sent in one of PDF, PWG Raster,  or
   JPEG format. Other formats are not accepted.

   This functionality is primarily for mobile devices running CUPS to not need a printer setup tool nor a collection of printer drivers and PPDs.

           CreateIPPPrinterQueues No
           CreateIPPPrinterQueues LocalOnly
           CreateIPPPrinterQueues Everywhere
           CreateIPPPrinterQueues AppleRaster
           CreateIPPPrinterQueues Everywhere AppleRaster
           CreateIPPPrinterQueues Driverless
           CreateIPPPrinterQueues All

   If  cups-browsed  is  automatically  creating print queues for native IPP network printers ("CreateIPPPrinterQueues Yes"), the type of queue to be created can be selected by the "IPP‐
   PrinterQueueType" directive. The "PPD" (default) setting makes queues with PPD file being created. With "Interface" or "NoPPD" the queue is created with a System  V  interface  script
   (Not supported with CUPS 2.2.x or later). "Auto" is for backward compatibility and also lets queues with PPD get created.

           IPPPrinterQueueType PPD
           IPPPrinterQueueType NoPPD
           IPPPrinterQueueType Interface
           IPPPrinterQueueType Auto

   The NewIPPPrinterQueuesShared directive determines whether a print queue for a newly discovered IPP network printer (not remote CUPS queue) will be shared to the local network or not.
   This  is only valid for newly discovered printers. For printers discovered in an earlier cups-browsed session, cups-browsed will remember whether the printer was shared, so changes by
   the user get conserved. Default is not to share newly discovered IPP printers.

           NewIPPPrinterQueuesShared Yes

   How to handle the print queues cups-browsed creates when cups-browsed is shut down:

   "KeepGeneratedQueuesOnShutdown No" makes the queues being removed. This makes sense as these queues only work while cups-browsed is running. cups-browsed has  to  determine  to  which
   member printer of a cluster to pass on the job.

   "KeepGeneratedQueuesOnShutdown  Yes"  (the default) makes the queues not being removed. This is the recommended setting for a system where cups-browsed is permanently running and only
   stopped for short times (like log rotation) or on shutdown. This avoids the re-creation of the queues when cups-browsed is restarted, which often causes a clutter  of  CUPS  notifica
   tions on the desktop.

           KeepGeneratedQueuesOnShutdown No

   If there is more than one remote CUPS printer whose local queue would get the same name and AutoClustering is set to "Yes" (the default) only one local queue is created which makes up
   a load-balancing cluster of the remote printers which would get this queue name (implicit class). This means that when several jobs are sent to this queue they get distributed between
   the printers, using the method chosen by the LoadBalancing directive.

   Note  that  the forming of clusters depends on the naming scheme for local queues created by cups-browsed. If you have set LocalQueueNamingRemoteCUPS to "DNSSD" you will not get auto
   matic clustering as the DNS-SD service names are always unique. With LocalQueueNamingRemoteCUPS set to "RemoteName" local queues are named as the CUPS queues on the remote servers are
   named and so equally named queues on different servers get clustered (this is how CUPS did it in version 1.5.x or older). LocalQueueNamingRemoteCUPS set to  "MakeModel"  makes  remote
   printers of the same model get clustered. Note that then a cluster can contain more than one queue of the same server.

   With  AutoClustering  set to "No", for each remote CUPS printer an individual local queue is created, and to avoid name clashes when using the LocalQueueNamingRemoteCUPS settings "Re‐
   moteName" or "MakeModel" "@<server name>" is added to the local queue name.

   Only remote CUPS printers get clustered, not IPP network printers or IPP-over-USB printers.

           AutoClustering Yes
           AutoClustering No

   Load-balancing printer cluster formation can also be manually controlled by defining explicitly which remote CUPS printers should get clustered together.

   This is done by the "Cluster" directive:

           Cluster <QUEUENAME>: <EXPRESSION1> <EXPRESSION2> ...
           Cluster <QUEUENAME>

   If no expressions are given, <QUEUENAME> is used as the first and only expression for this cluster.

   Discovered printers are matched against all the expressions of all defined clusters. The first expression which matches the discovered printer determines to which cluster it  belongs.
   Note that this way a printer can only belong to one cluster. Once matched, further cluster definitions will not checked any more.

   With  the first printer matching a cluster's expression a local queue with the name <QUEUENAME> is created. If more printers are discovered and match this cluster, they join the clus‐
   ter. Printing to this queue prints to all these printers in a load-balancing manner, according to to the setting of the LoadBalancing directive.

   Each expression must be a string of characters without spaces. If spaces are needed, replace them by underscores ('_').

   An expression can be matched in three ways:

       1. By the name of the CUPS queue on the remote server
       2. By make and model name of the remote printer
       3. By the DNS-SD service name of the remote printer

   Note that the matching is done case-insensitively and any group of non-alphanumerical characters is replaced by a single underscore.

   So if an expression is "HP_DeskJet_2540" and the remote server reports "hp Deskjet-2540" the printer gets matched to this cluster.

   If "AutoClustering" is not set to "No" both your manual cluster definitions will be followed and automatic clustering of equally-named remote queues will be performed.  If  a  printer
   matches  in  both  categories the match to the manually defined cluster has priority. Automatic clustering of equally-named remote printers is not performed if there is a manually de
   fined cluster with this name (at least as the printers do not match this cluster).

   Examples:

   To cluster all remote CUPS queues named "laserprinter" in your local network but not cluster any other equally-named remote CUPS printers use  (Local  queue  will  get  named  "laser‐
   printer"):

           AutoClustering No
           Cluster laserprinter

   To cluster all remote CUPS queues of HP LaserJet 4050 printers in a local queue named "LJ4050":

           Cluster LJ4050: HP_LaserJet_4050

   As DNS-SD service names are unique in a network you can create a cluster from exactly specified printers (spaces replaced by underscores):

           Cluster hrdep: oldlaser_@_hr-server1 newlaser_@_hr-server2

   The  LoadBalancing  directive  switches  between  two methods of handling load balancing between equally-named remote queues which are represented by one local print queue making up a
   cluster of them (implicit class).

   The two methods are:

   Queuing of jobs on the client (LoadBalancing QueueOnClient):

   Here we queue up the jobs on the client and regularly check the clustered remote print queues. If we find an idle queue, we pass on a job to it.

   This is also the method which CUPS uses for classes. Advantage is a more even distribution of the job workload on the servers (especially if the printing speed of the servers is  very
   different),  and if a server fails, there are not several jobs stuck or lost. Disadvantage is that if one takes the client (laptop, mobile phone, ...) out of the local network, print
   ing stops with the jobs waiting in the local queue.

   Queuing of jobs on the servers (LoadBalancing QueueOnServers):

   Here we check the number of jobs on each of the clustered remote printers and send an incoming job immediately to the remote printer with the lowest amount of jobs in its queue.  This
   way no jobs queue up locally, all jobs which are waiting are waiting on one of the remote servers.

   Not  having jobs waiting locally has the advantage that we can take the local machine from the network and all jobs get printed.  Disadvantage is that if a server with a full queue of
   jobs goes away, the jobs go away, too.

   Default is queuing the jobs on the client as this is what CUPS does with classes.

           LoadBalancing QueueOnClient
           LoadBalancing QueueOnServers

   With the DefaultOptions directive one or more option settings can be defined to be applied to every print queue newly created by cups-browsed. Each option is supplied as one  supplies
   options  with  the  "-o" command line argument to the "lpadmin" command (Run "man lpadmin" for more details). More than one option can be supplied separating the options by spaces. By
   default no option settings are pre-defined.

   Note that print queues which cups-browsed already created before remember their previous settings and so these settings do not get applied.

           DefaultOptions Option1=Value1 Option2=Value2 Option3 noOption4

   The AutoShutdown directive specifies whether cups-browsed should automatically terminate when it has no local raw queues set up pointing to any discovered remote printers or  no  jobs
   on  such  queues  depending  on AutoShutdownOn setting (auto shutdown mode). Setting it to "On" activates the auto-shutdown mode, setting it to "Off" deactivates it (the default). The
   special mode "avahi" turns auto shutdown off while avahi-daemon is running and on when avahi-daemon stops. This allows running cups-browsed on-demand when avahi-daemon is  run  on-de
   mand.

           AutoShutdown Off
           AutoShutdown On
           AutoShutdown avahi

   The  AutoShutdownOn  directive  determines  what  event cups-browsed considers as inactivity in auto shutdown mode. "NoQueues" (the default) means that auto shutdown is initiated when
   there are no queues for discovered remote printers generated by cups-browsed any more. "NoJobs" means that all queues generated by cups-browsed are without jobs.

           AutoShutdownOn NoQueues
           AutoShutdownOn NoJobs

   DebugLogFileSize defines the maximum size possible (in KBytes) of the log files (cups-browsed_log and cups-browsed_previous_logs) that is created using cups-browsed in  the  debugging
   mode.  Setting its value to 0 would turn off any restriction on the size of the file.

           DebugLogFileSize 300

   The  AutoShutdownTimeout  directive  specifies  after  how many seconds without local raw queues set up pointing to any discovered remote printers or jobs on these queues cups-browsed
   should actually shut down in auto shutdown mode. Default is 30 seconds, 0 means immediate shutdown.

           AutoShutdownTimeout 20

   NotifLeaseDuration defines how long the D-BUS subscription created by cups-browsed in cupsd will last before cupsd cancels it. The default value is 1 day in seconds - 86400. The  sub
   scription renewal is set to happen after half of NotifLeaseDuration passed. The D-BUS notifications are used for watching over queues and doing specific actions when a D-BUS notifica
   tion comes.

           NotifLeaseDuration 86400

SEE ALSO

   cups-browsed(8)

   /usr/share/doc/cups-browsed/README.gz

AUTHOR

   The authors of cups-browsed are listed in /usr/share/doc/cups-browsed/AUTHORS.

   This manual page was written for the Debian Project, but it may be used by others.

                                                                                     29 June 2013                                                                     cups-browsed.conf(5)