hi,

one of my servers rebooted, there is only ssh and tomcat listening to outside world. ssh is secured but i dont know how could someone intrude to server via tomcat, change something and reboot.
i checked log files, there is no single line of log in messages log for days which is scary.
i checked tripwire report, unfortunately tripwire didnt include webpage directory but the other system files are clean.

what should i checked? this is accounting server and need more attention.

looking for your guides.

I would first ensure that measures are in place (after all this is an "accounting server") that provide an audit trail like running the audit service with a relevant rule set, ensuring user login and connection logging is in place, enabling remote kernel dumps, set up hardware and service monitoring and complement it with remote logging. Then I'd look at possible hardware problems because until you have checked all files and user login records on the server and correlated log entries with file modification times, user login records and (if possible) any logging proxies, routers or adjacent machines provide there's no clue this could be a compromise of security.

thank you, i checked with the company that host the server, they said it was a maintenance issue and they didnt clear out more, but i dont know how they could reboot the system without password.

check out logs that might give you hint.

or type: dmesg | tail -f

check out if it will give you something.

The OP already said "i checked log files, there is no single line of log in messages log" so what log file(s) specifically?


The kernel ring buffer gets cleared on boot.

If they didn't contact you beforehand or reported afterwards themselves then it indeed is a maintenance issue ;-p


Is it a virtual or physical machine?

i checked dmesg, security, mail log files, no need for checking ssh and fail2ban as they are secure. this is a vm.

actually the server is giving service to their own company.


thanks for following

That's it then. They just access some dom0 maintenance interface and force a reboot.

Moved: Since this isn't a security issue this thread is more suitable in the Newbie Forum Name and has been moved accordingly to help your thread/question get the exposure it deserves.