[mod_python] [Pywebsvcs-talk] Spontaneous 404

Joseph Bernhardt wrote, at 03/12/2008 10:55 AM:
> We’re running a LAMP server (RHEL) with Python v2.5 and mod_python 
> v3.1.3 to control some smaller, web-based transactions for our company 
> (publisher handler; if that makes any difference).  Larger transactions 
> are run in combination between client applications contacting either 
> Python apps or the MySQL database directly on the server.  
> Unfortunately, these large transactions are processing giants that cause 
> problems with such an underrated server.   We realize this is the blunt 
> of our problem and are working on upgrades which may help in the future. 
> 
> My question deals with suggestions on what to do in the mean time.   I’m 
> not sure if this would be an Apache or mod_python problem, but am 
> assuming  the latter.   During processing of a large server application 
> (either MySQL or Python oriented), requests made to our mod_python 
> enabled websites are spontaneously returned as 404 errors.  Has anyone 
> else experienced such odd behavior?  And, if so, how was it dealt with?  
> One would assume that a 404 error would indicate either a problem with 
> the mod_python application itself, or in that the file does not exist on 
> the server.  But, this behavior (working correctly more than half the 
> time) suggests something else.

404 errors are either traversal errors or outright incorrect requests. 
Look in your logs to see if there is a common pattern with the 404 
requests. If possible, access them directly to see if they work. If you 
believe that the same URL works randomly, find evidence of success & 
failure for the same request in the logs. Don't rule out a problem with 
the application itself, especially if it incorrectly constructs relative 
URLs based on user input (such as the presence or absence of closing 
slashes).