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Throttling Down

Date:  Mon, 20th-Dec-2004prevnext

Tags: Apache, SysAdmin, Urban Mainframe

The Urban Mainframe was effectively offline for almost an hour last night when an overly aggressive bot flooded the web-server with more concurrent requests than it can handle.

I have now installed the mod_throttle bandwidth and request throttling module to act as a first line of defence against future "attacks".

Unfortunately, I've found the documentation for mod_throttle to be a little vague and Googling has only added to my confusion. Thus it is perfectly possible that strange things will happen as I experiment with and tune the mod_throttle configuration. It is probably going to take some time to get it right. So please excuse any aberrations and, where possible, let me know about any glitches (via the comments, IM or email).

If there are any mod_throttle gurus out there, then please get in touch - I really need your help!

UPDATE: 22nd December, 2004 (00:32) - Installing mod_throttle turned out to be a really bad move. My server has repeatedly gone down for the past 7 or 8 hours and, during its sporadic uptime, locked out many visitors with completely unjustified (and seemingly random) "Service Unavailable" errors. Apache/mod_throttle spawned hundreds of "defunct" httpd processes and the server basically died.

mod_throttle no longer lives on this server!

Sorry for all the downtime people.

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