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The Shibboleth Apache module logs by default to $prefix/var/log/httpd/native.log. This file must be writable by Apache, which may require that you set its directory's ownership and/or permissions to allow write access by the user Apache is configured to run under. You may also choose to change the location of the file, by modifying the log4j.appender.native_log.fileName setting in $prefix/etc/shibboleth/native.logger.
For information on configuring Shibboleth to protect content, see the Shibboleth wiki.
You will probably also want to customize the error pages and support contact information listed in the Errors element in $prefix/etc/shibboleth/shibboleth.xml (search for "You should customize these pages!"), e.g.:
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