I have had an NCSA server up and running on a SPARC (with SunOS 4.1.3)
for over two years now without any problems worth mentioning.
But lately it more and more often just returns error 404:
"requested URL not found" in response to perfectly valid requests
for ordinary html, gif or jpg files. This week this problem has
reached dimensions where it turns into a real nuisance.
When this happens, which is now about once for every five or six
http requests, and the requester sends the same request again,
e.g. with a "reload" command in a Netscape browser, the requested file
is always delivered. So why does the first attempt fail so often?
The server has not been recompiled or restarted for months, and
the problem has not been of a noticeable size before now.
It may or may not be relevant to the problem, but reading the
access_log file I have noticed that on failed requests, the
IP address of the requester is not translated into a hostname,
but when the request is served successfully, it is.
silikon.pvv.ntnu.no - - [30/Oct/1996:16:29:21 +0100] "GET /~ulf/angst.html HTTP/1.0" 200 721
188.8.131.52 - - [30/Oct/1996:16:29:22 +0100] "GET /~ulf/pic/album1/angst95.jpg HTTP/1.0" 404 -
silikon.pvv.ntnu.no - - [30/Oct/1996:16:32:22 +0100] "GET /~ulf/pic/album1/angst95.jpg HTTP/1.0" 200 108158
I'd like to receive suggestions to what may be the cause of this
problem, or how I can investigate it further.