All providers unknown


None of the providers shows up. I can see it says: “Note: Unknown provider means the IP address could not be looked up. See this faq.” which provides this:

Piwik uses a special php function (gethostbyaddr) to request the hostname associated to a given IP. For example, the function would return “” and Piwik would categorize the visitor as using the provider “Comcast”. Sometimes however, for specific IPs or when the function times out, Piwik doesn’t know which provider the visitor is using and will simply report “Unknown”.

But I don’t understand what I can do with this information. How do I fix it so it shows the providers?