I'd try traceroute next. It should get you close enough to tell who owns that IP. If not, you can often e-mail the last network that does RDNS and ask who owns the given IP. -- Brian On Thu, 06 Jul 2000, Edouard Soriano wrote: > Hi guys, > > We have set up a Firewall based on Linux. Since several days there are > some IP address trying to enter > using telnet. > > One of them was found using nslookup. We sent a warning message to the > ISP manager and they stopped. > > But the other is trying like crazy requesting telnet who are rejected by > the security rules. > > This address in unknowed by nslookup. > > Any idea about how to catch this #@]|]]!! unfair person ? > > Thanks > > - > : send the line "unsubscribe linux-net" in > the body of a message to majordomo@vger.rutgers.edu - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.rutgers.edu