Lots of 400 errors in my logs

Why and should I do anything?

[bouncybunny]

I get hundreds of daily 400 errors in my logs, as shown below, and I was wondering why this might be and whether I should be doing anything about it.

Thanks.

[Thu Mar 14 09:29:46 2007] [error] [client 000.000.000.000] File does not exist: /home/user/public_html/400.shtml

[benevolent001]

10.4.1 400 Bad Request
The request could not be understood by the server due to malformed syntax. The client SHOULD NOT repeat the request without modifications.

The above is defination of 400 error , now compare with your error logs , i guess you must be safe

[jdMorgan]

A 400 error means that the client sent an invalid request -- Not much you can do about that.

But the log entry you posted indicates that you've got a second problem: You have declared --in your control panel, in your server config, or in one or more .htaccess files-- that you have a custom 400-Error handling page, but the page that you declared does not exist on your site. You should either put up a custom 400 error page "/400.shtml", or remove the declaration from wherever you made it.

The "raw" declaration is made using Apache's ErrorDocument directive, documented in Apache Core [httpd.apache.org], and will likely look like this:

ErrorDocument 400 /400.shtml

Jim

[bouncybunny]

Thanks for that. I'll check my settings out.

If I am getting this amount of 400 requests, generally a few dozen from each IP address within a few seconds, could this signify anything sinister?

Thanks again.

[Keniki]

A very good question, is this a possible alert?