Hi, The CUPS web interface in my Guix system hangs when loading the admin page, making it cumbersome to manage CUPS printers and settings. The cause appears to be that the web interface CGI scripts expect a config file in the wrong location. HOW TO REPRODUCE: My system is running Guix commit 290b55c55a5 with the following CUPS configuration: (service cups-service-type (cups-configuration (web-interface? #t) (log-level 'debug) (extensions (list cups-filters foomatic-filters hplip-minimal)))) I load http://localhost:631/admin in a browser (Icecat). Expected behavior is for the page to load immediately. Actual behavior is the page hangs for a minute or two, displaying a blank screen. Eventually the expected Administration page loads, but is missing some controls and displays "Unable to open cupsd.conf file: Success." DETAILS: Excerpt from /var/log/cups/error_log is attached. Note especially CUPS_SERVERROOT=/etc/cups. Output of ‘ps -ef | grep cupsd’: root 6374 1 0 00:29 ? 00:00:01 /gnu/store/wxg6fa0d1hlna6gg2nrn51fkq68q7fy9-cups-2.3.1/sbin/cupsd -f -c /gnu/store/6i13apvx94y7q61rh3hsj7fhjb6brgf4-cupsd.conf -s /gnu/store/nxzmy9s6inia31wvhrcrzcf66rb4v4pp-cups-files.conf Output of ‘sudo strace -p `pidof cupsd` -f -e file’ while refreshing the Administration page contains a number of entries like this: [pid 8423] access("/etc/cups/cupsd.conf", R_OK) = -1 ENOENT (No such file or directory) The directory /etc/cups exists but contains only ssl/ and ppd/ subdirectories, no cupsd.conf. If I create a symlink /etc/cups/conf.d -> /gnu/store/6i13...-cupsd.conf, the Administration page now loads without any issue. In addition, I noticed that (per Guix manual) the server-root field of the CUPS service’s files-configuration section defaults to /etc/cups. If I set that field to /gnu/store/wxg6...-cups-2.3.1/etc/cups (see the cupsd command line above) then run ‘guix system reconfigure’ and restart cupsd, the web interface again works as expected. Finally, note that the ServerRoot field of /gnu/store/nxzm...-cups-files.conf is set to /gnu/store/wxg6...-2.3.1/etc/cups (again see cupsd command line above). COMMENTARY: From examining the CUPS sources, it appears the web admin interface expects to find cupsd.conf in CUPS_SERVERROOT solely to make the "Edit Configuration File" feature work. This feature doesn't seem very useful on Guix since the config file lives in the (read-only) store. However, the file still needs to be present in order to satisfy the admin page CGI script and keep it from hanging. Thus, perhaps the problem could be solved by having the service make a symlink /etc/cups/cupsd.conf pointing at its generated cupsd.conf file. Thanks, Jacob