mmm,... ???
just guessing here that adavin installed Citadel wrongly, that is - on top of Apache as if it were stand-alone, and/or perhaps wrongly chose 'option to integrate'? and thus when the linode rebooted "start page become [sic] Citadel". Somehow things kept running for adavin until the system rebooted. If so, then adavin, you're not too far from doing things correctly - but you will need to try again, ...
This from the Linode Library Citadel install guide ::
Quote:
We assume you have followed the getting started guide as a prerequisite. We also assume you want to run Citadel by itself on this server, using port 80 or port 443 for browser-based access.
Please note: If you intend to install Citadel alongside a pre-existing web server package, do not select the option to integrate with that web server during setup. Select the option for "internal" when asked about web server integration, and be sure to specify unique ports for Citadel (such as 8080 for HTTP and 4343 for HTTPS).