I looked at my logs from amazon ec2 instance and found the following lines:
220.127.116.11 - - [29/Mar/2014:08:50:52 +0000] "XGET /web-console/ServerInfo.jsp HTTP/1.0" 501 418 "-" "-" 18.104.22.168 - - [29/Mar/2014:08:50:52 +0000] "XGET /jmx-console/HtmlAdaptor HTTP/1.0" 501 415 "-" "-"
I looked at http status codes and 501 means.
501 Not Implemented
The server either does not recognize the request method, or it lacks the ability to fulfill the request. Usually this implies future availability (e.g., a new feature of a web-service API).
I checked that such files and even parenting directories do not exist in my
/var/www and therefore I do not understand why it shows 501 and not 404.
I googled about these particular names (ServerInfo.jsp and HtmlAdaptor) but did not find anything that I can properly understand.
I found also similar issues in my
error.log file (due to stupidity I truncated the logs...).
Do not know if this is helpful, but nothing was installed on the server except of git and some updates.
Does this sound like an intrusion or am I overreacting? What can these
501 means (wiki explanation are not really helpful to me)?