I've contacted support about this but they offered no solution, so I was hoping someone more knowledgeable could give me some insight into why this might happen:
Sometimes when I attempt to access a subdomain on my site, a subdomain that exists and has been accessed before many times, I'm greeted with the "Server not found" or "This site cannot be reached" error page.
When I put in a support ticket about this, Support responded that they could access the subdomain just fine from their location. The subdomain is also accessible from other machines, albeit inconsistently.
What could possibly cause this behavior?