root@ubuntu:/home/christopher# tcpdump -i eth0 'tcp port 8888' tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes 13:05:32.620531 IP 192.168.0.170.1553 > 192.168.0.190.8888: S 851167939:851167939(0) win 32768 13:05:35.635588 IP 192.168.0.170.1553 > 192.168.0.190.8888: S 851167939:851167939(0) win 32768 13:05:41.674600 IP 192.168.0.170.1553 > 192.168.0.190.8888: S 851167939:851167939(0) win 32768 3 packets captured 3 packets received by filter 0 packets dropped by kernel LOCAL: root@ubuntu:/home/christopher# tcpdump -i lo 'tcp port 8888' tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on lo, link-type EN10MB (Ethernet), capture size 96 bytes trying to telnet to itself both on localhost and the eth0 interface from the ubuntu box: root@ubuntu:/home/christopher# telnet localhost 8888 Trying 127.0.0.1... telnet: Unable to connect to remote host: Connection refused root@ubuntu:/home/christopher# telnet 192.168.0.190 8888 Trying 192.168.0.190... telnet: Unable to connect to remote host: Connection refused