Maybe a bit drastic but it sometimes did wonders for me when a server was under attack, is to place a .htaccess login on the main directory. You can simply list the user/pass in the login prompt, but that will remove all bots and other unwanted visitors.
Also disable any hotlinking and/or RSS feeds.
I can't do the first suggestion, because I only have access to the ACP, no direct root access. I'll look into the other ideas, though.
Quote:
Originally Posted by Mooff
Really drastic way:
Use a very lightweight mobile style which doesn't show avatars, signatures and almost all images as the default style for all users.
(we used a 58k style when we had our spam-friday, a day where we removed the posting limitations for 10minutes and encouraged our users to give it a shot, once we grew bigger it crashed our server everytime, so we had to stop doing that )
Anyway for vb4: https://vborg.vbsupport.ru/showthread.php?t=249277
Idea is to reduce the http requests (pictures and javascript) and send less data, so even under massive server load the forum would still manage to load in a reasonable time.