You can enable search indexing by going into the General Settings page and toggling Enable search. The Search index file field must be filled out to specify the desired directory where the search index will be stored. Usually this will be a directory under your site directory.
Now you will need to set up a scheduled command to run periodically to
update the search index. On Linux or other Unix-based systems with
cron, you can install the provided
crontab file. This is
conf/cron.conf under your site directory. For
example, to install the crontab for the current user, type:
$ crontab /path/to/site/conf/cron.conf
Make sure the user with the crontab has permissions to write to the search index file you specified above, as well as the search index’s parent directory.
The default crontab will perform an index update every 10 minutes.
You will want to perform one full index before you can use this. To do this, type the following as the user who owns the cronjob:
$ rb-site manage /path/to/site rebuild_index
For more information on generating search indexes, see the section on the Search Indexing management command.
Users should now be able to use the search box located on any page. See the documentation on Full-Text Search to see what types of things you can search for.