Multisite will not enable when using WPMU manual instructions on Rackspace Cloud server

I am trying to enable Multisite according to the instructions for “Creating a network by enabling WordPress Multisite” in the WPMU manual found here:

I have problems with the following steps:

5. There is no “public_html” folder; files are in web/content folder since it is installed on a Rackspace Cloud server
6. After copying/overwriting wp-config.php file in web/content folder, Network menu option does not appear in Tools menu

Please let me know if there's something I'm missing or what troubleshooting I need to perform.