On Apr 17, at 04:28 PM, [email protected] wrote: > > Heya.. > > Yesterday someone "attacked" by box by connection to several ports.. In > other words, a simple portscan.. yet, since my box has "log_in_vain" > enabled, so it tries to log everything to /var/log/messages, since the > logfile got full and the size went over 100K, it tried to rotate the log > to save diskspace. > > (Apr 16 21:00:00 omikron newsyslog[32137]: logfile turned over due to > size>100K) > > My server box is a Intel Celeron 733Mhz, 384Mb of RAM.. yet it's slow from > time to time since I only run ATA66 due to the old motherboard. When this > "attack" occured yesterday, the box almost died and the box were working > 100%.. all users who were logged in got "spammed" since the default > *.emerg in /etc/syslog.conf is set to "*" .. If you're running a relatively slow bus, chances are you could (maybe even "have"?) experienced this already by a completely different set of circumstances, but didn't put it together? > Isn't this a quite simple way of making a DoS attack against a system? My > box is running on 10mbit and the person who scanned my server were > connecting from a cable connection... > [SNIP] Assuming the attacker knew you had a slower bus, were running FreeBSD, had log_in_vain turned on, and ... ? > I would be glad if anyone could tell me how to solve this and/or how to > make sure it doesn't happen again. Seems to me you're hampered by your hardware, and this episode is/was just the latest symptom. Moving /var to another physical drive on a different channel will help. So would tuning /etc/syslog.conf. Of course, so would turning off the log_in_vain knob (though I like it on, too). A new ATA adapter isn't all that expensive anymore, and would boost performance overall. HTH, Dave -- ______________________ ______________________ \__________________ \ D. J. HAWKEY JR. / __________________/ \________________/\ [email protected] /\________________/ http://www.visi.com/~hawkeyd/ _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-security To unsubscribe, send any mail to "[email protected]"