cups-browsed

cups-browsed [ OPTIONS ]

-c file
    Specifies an alternate configuration file for cups-browsed.

-D
    Enables debug mode, logging extensive information to standard error.

-d
    Daemonizes the process, running it in the background (default behavior).

-f
    Runs in the foreground, preventing daemonization.

-h
    Displays a help message and exits.

-L level
    Sets the logging level (e.g., debug, info, warn, error).

-v
    Displays the version information of cups-browsed and exits.

cups-browsed is a daemon that discovers and manages network printers for the Common Unix Printing System (CUPS). Its primary function is to browse for shared CUPS printers and IPP (Internet Printing Protocol) printers advertised on the local network, primarily using Bonjour/DNS-SD (mDNS) or the legacy CUPS browsing protocol.

Upon discovering new printers, cups-browsed can automatically create local print queues for them, making them immediately available to users on the system without manual configuration. It also monitors the availability of these printers, updating or removing queues as printers appear or disappear from the network. This automation simplifies printer setup significantly in network environments, especially for desktop users who might not have administrative privileges to configure printers manually. It typically runs in the background and is an essential component for seamless network printing discovery.

cups-browsed relies heavily on network services like Bonjour/DNS-SD (mDNS) for discovery. Proper firewall configuration is crucial to allow UDP ports 5353 (mDNS) and 631 (IPP/CUPS) for browsing and printing.

Its effectiveness can be limited by network topology, especially across different subnets without a configured mDNS reflector or other discovery mechanisms. While it automates queue creation, it may not always select the optimal driver or configuration for complex printers, sometimes requiring manual adjustment via lpadmin.

/etc/cups/cups-browsed.conf
This file controls cups-browsed's behavior, including which browsing protocols to use, which network interfaces to monitor, and whether to auto-create local queues. It's crucial for fine-tuning its operation in specific network environments.

cups-browsed works in conjunction with the main cupsd daemon. While cupsd handles print jobs and core printer management, cups-browsed focuses solely on the discovery and dynamic creation/removal of printer queues in cupsd's configuration, ensuring that available network printers are always reflected locally.

cups-browsed was developed as part of the CUPS (Common Unix Printing System) project, which was originally created by Easy Software Products. CUPS became the standard printing system for most Linux distributions and macOS.

After Apple acquired CUPS development in 2007, the project continued to evolve. With Apple's shift in focus, the OpenPrinting organization took over stewardship of CUPS development for Linux and other Unix-like systems. cups-browsed emerged to address the need for automatic printer discovery and queue management, especially with the increasing prevalence of network-advertised printers using IPP and Bonjour, simplifying printer setup for end-users.

cupsd(8), lpadmin(8), avahi-daemon(8), printers.conf(5)