Best server status code for SEs if a site goes over bandwidth.

[rfgdxm1]

This issue came up elsewhere in a thread about a clueless website host who if a site exceeded allowed bandwidth was sending an error message stating that, along with a 200 status code indicating everything was OK. Which would obviously be catastrophic for search engines because they would just think this was the new content of the site because of that 200 status code. What I was wondering is what is the best and most appropriate error code for a server to return in this case? Something in the 400 series? 500 series?

[jdMorgan]

I found this tucked away on my hard drive:

503 Service Unavailable

The server is currently unable to handle the request due to a temporary overloading or maintenance of the server. The implication is that this is a temporary condition which will be alleviated after some delay. If known, the length of the delay may be indicated in a Retry-After header. If no Retry-After is given, the client SHOULD handle the response as it would for a 500 response.

Note: The existence of the 503 status code does not imply that a server must use it when becoming overloaded. Some servers may wish to simply refuse the connection.

Jim