Re: Bug#137340: ITP: ip2host -- Resolve IPs to hostnames in web server logs

[Cyrille Chepelov <cyrille@chepelov.org>]

Le Fri, Mar 08, 2002, à 04:43:55PM +0000, Wilmer van der Gaast a écrit:

> Hmm... If webserver == Apache, the webserver does this already. I see a
> lot of hostnames in my /var/log/apache/access.log, almost no IP
> addresses. So what does ip2host do? Some nifty caching?

<hat type="explainer"> <!-- yes, I made up that word -->
A lot of webservers have the option of disabling this resolution, to save
the load and shorten the total transaction time. Doing the resolution as a
postprocessing of the logs can help reduce the total DNS time by batching
the resolution of clients into a single reverse resolution per client per
postprocess run (as opposed to at worst one resolution per hit, possibly
cached a couple minutes by the local DNS or by an extra piece of bloat in
the web server proper. Besides, libresolv has timing characteristics which
can be... annoying for a critical process).
</hat>

	-- Cyrille

	
-- 
Grumpf.