Don’t have the answer to this yet, but it sure makes me really really curious as to the cause.
In my web server access logs, I get plenty of entries that look like this:
220.127.116.11 - - [02/Oct/2009:14:20:55 +0800] "-" 400 0 "-" "-"
That means that these IP addresses have been connecting to my server via a particular domain, without sending any request whatsoever or so it seems. And I get a LOT of accesses from Singnet IP addresses (18.104.22.168/16 range) daily.
Have contacted them on this, but no answers as yet. And the only answer from a forum was that it’s probably load balancer generated traffic (doesn’t explain why I get many many requests from an entire Class C worth of IP addresses).
Not sure whether it was this thing that caused my 1Portfolio account to overuse server resources, since Apache is known to fork a new process for every new incoming connection, as opposed to web servers like Nginx. (And I’m still pissed at how they did NOT contact me whatsoever when they had to terminate my account immediately due to the resource overuse)
If anyone has answers/possibilities I’d sure like to hear and discuss on them!