The Apache configuration for this web server instance runs as the lp print service user, which provides enough privileges to support all of the existing IPP operations, but limits access to print service specific resources. The listening service runs as its own web server instance, specifically configured to support IPP, which is intended to minimize potential security risks.
On the server-side, IPP configuration changes are made to the /etc/apache/httpd-standalone-ipp.conf file. On the client-side, IPP configuration changes are made to the /etc/printers.conf file.
If you make any configuration changes, you need to restart the service to load the new configuration. For more information, see How to Restart the Print Scheduler.
The IPP listening service configuration file, /etc/apache/httpd-standalone-ipp.conf, is like any normal Apache 1.3 configuration file. The configuration files takes any Apache 1.3 configuration directives that you want to use.
The default configuration includes the following features:
Listening on port 631.
Loading of a minimal set of Apache modules.
Enabling all supported IPP operations at the /printers/ path, for example ipp://server/printers/, without requiring authentication.
The default operations that are enabled for/printers/ is limited to a set of operations that poses less of a security risk. However, all operations are enabled at the /admin/ path, for example ipp://server/admin/, with basic authentication required.
The mod_ipp Apache configuration options to choose from are:
ipp-conformance – Selects the level of protocol checking. The default is automatic, allowing maximum client interaction.
ipp-operation – Allows you to selectively enable or disable IPP operation support for one more IPP operations.
ipp-default-user – Selects the user name to use when contacting the local print service.
The default is lp user, which allows for more functional proxying.
ipp-default-service – Selects the default print service where print requests are directed.
The default is the lpsched daemon.
Conformance checking types are:
Automatic – Only check that the requested operation is supported by the protocol listener, which is the default.
1.0 – Check that the request conforms to IPP, 1.0.
1.1 – Check that the request conforms to IPP, 1.1.