source --- http://www.wellho.net/mouth/2063_Internal-Dummy-Connections-on-Apache-httpd.html
Is your Apache httpd log file 'full' of entries like this?xx.xxx.xx.xx - - [02/Mar/2009:05:08:45 +0000] "OPTIONS * HTTP/1.0" 200 - "-" "Apache/2.2.9 (Unix) PHP/5.2.6 (internal dummy connection)"
What causes them?
Your web keeps a number of spare 'slots' open to process new incoming requests, opening them up ahead of growing traffic. And at times that traffic is dropping off, it closes spare slots to allow memory to be released to other system users. This dummy connection / request is used to signal to a slot that it should shut-down, so you'll find a series of these messages cropping up as traffic falls.
Should I worry about them?
Not very much. Some of them are to be expected; if there are a very large number of them, though, it may be worth you altering some of your server settings - see this previous article for a description of how the slots are opened and closed.
Can I eliminate the from my logs?
Yes - add something like:SetEnvIf Remote_Addr "xx/.xxx/.xx/.xx" dontlog
to your log file, and update your logging directive to use that setting:CustomLog /var/log/apache2/access_log combined env=!dontlog
There's more detail of how this configuration change works at this off site resource, but bear in mind that you'll be fixing a symptom rather than curing an issue if you simply stop logging huge quantities of these messages.
The IP address given will be your server's own IP address. If it's someone else's, then THAT would be a concern!
(written 2009-03-02)
A601 - Web Application Deployment - Apache httpd - an overview
[2186] An FAQ on the Apache httpd and Apache Tomcat web servers, and on using them together - (2009-05-17)
[2077] Why put Apache httpd in front of Apache Tomcat - (2009-03-12)
[2054] Tuning httpd / the supermarket checkout comparison - (2009-02-26)
[2038] Sticky Sessions with mod_jk (httpd to Tomcat) - (2009-02-12)
[2016] Apache httpd and Apache Tomcat miscellany - (2009-01-30)
[1897] Keeping on an even keel - (2008-11-21)
[1593] Keep the client experience easy - single server contact point - (2008-03-27)
[1265] Apache, Tomcat, Jakarta, httpd, web server - what are they? - (2007-07-13)
[924] The LAMP Cookbook - Linux, Apache, MySQL, PHP / Perl - (2006-11-13)
[659] Web Application Components - (2006-03-28)
[576] Why run two different web servers - (2006-01-25)