LaMont Jones a écrit : > On Sun, Oct 29, 2006 at 04:37:09PM +0100, Fabrice Dagorn wrote: > >> Architecture : ARM >> Kernel Version : 2.6.16 >> Nmap does not work on my NSLU2 (Debian testing). >> It works on localhost, but nowhere else. >> > > What does tcpdump show as the activity during the nmap 192.168.2.251? > > lamont > > tcpdump was running during this test :
mail:~# nmap 192.168.2.251 -P0 Starting Nmap 4.11 ( http://www.insecure.org/nmap/ ) at 2006-10-30 19:46 CET Nmap finished: 1 IP address (0 hosts up) scanned in 0.478 seconds mail:~# nmap 192.168.2.251 Starting Nmap 4.11 ( http://www.insecure.org/nmap/ ) at 2006-10-30 19:46 CET Note: Host seems down. If it is really up, but blocking our ping probes, try -P0 Nmap finished: 1 IP address (0 hosts up) scanned in 0.484 seconds mail:~# ping 192.168.2.251 PING 192.168.2.251 (192.168.2.251) 56(84) bytes of data. 64 bytes from 192.168.2.251: icmp_seq=1 ttl=128 time=4.40 ms 64 bytes from 192.168.2.251: icmp_seq=2 ttl=128 time=2.58 ms --- 192.168.2.251 ping statistics --- 2 packets transmitted, 2 received, 0% packet loss, time 1006ms rtt min/avg/max/mdev = 2.585/3.494/4.404/0.911 ms mail:~# and it answered (laptop-old is the name of 192.168.2.251): mail:~# tcpdump -i eth0 | grep 'laptop' tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes 19:46:28.404845 IP laptop-old.home.net > nslu2.home.net: ICMP echo reply, id 20017, seq 1, length 64 19:46:29.409783 IP laptop-old.home.net > nslu2.home.net: ICMP echo reply, id 20017, seq 2, length 64 105 packets captured 105 packets received by filter 0 packets dropped by kernel mail:~# but with nmap localhost : mail:~# tcpdump -i lo (...) 19:52:17.409681 IP localhost.localdomain.350 > localhost.localdomain.56186: R 0:0(0) ack 3687722494 win 0 19:52:17.413976 IP localhost.localdomain.56186 > localhost.localdomain.mtp: S 3687722493:3687722493(0) win 4096 <mss 1460> 19:52:17.414124 IP localhost.localdomain.mtp > localhost.localdomain.56186: R 0:0(0) ack 3687722494 win 0 19:52:17.418760 IP localhost.localdomain.56186 > localhost.localdomain.400: S 3687722493:3687722493(0) win 3072 <mss 1460> 19:52:17.418928 IP localhost.localdomain.400 > localhost.localdomain.56186: R 0:0(0) ack 3687722494 win 0 19:52:17.422855 IP localhost.localdomain.56186 > localhost.localdomain.47557: S 3687722493:3687722493(0) win 2048 <mss 1460> 19:52:17.423006 IP localhost.localdomain.47557 > localhost.localdomain.56186: R 0:0(0) ack 3687722494 win 0 19:52:17.425630 IP localhost.localdomain.56186 > localhost.localdomain.299: S 3687722493:3687722493(0) win 2048 <mss 1460> 19:52:17.425775 IP localhost.localdomain.299 > localhost.localdomain.56186: R 0:0(0) ack 3687722494 win 0 19:52:17.428357 IP localhost.localdomain.56186 > localhost.localdomain.fax: S 3687722493:3687722493(0) win 4096 <mss 1460> 19:52:17.428523 IP localhost.localdomain.fax > localhost.localdomain.56186: R 0:0(0) ack 3687722494 win 0 19:52:17.431146 IP localhost.localdomain.56186 > localhost.localdomain.941: S 3687722493:3687722493(0) win 4096 <mss 1460> 19:52:17.431298 IP localhost.localdomain.941 > localhost.localdomain.56186: R 0:0(0) ack 3687722494 win 0 19:52:17.434537 IP localhost.localdomain.56186 > localhost.localdomain.61440: S 3687722493:3687722493(0) win 3072 <mss 1460> 19:52:17.434710 IP localhost.localdomain.61440 > localhost.localdomain.56186: R 0:0(0) ack 3687722494 win 0 19:52:17.437311 IP localhost.localdomain.56186 > localhost.localdomain.578: S 3687722493:3687722493(0) win 4096 <mss 1460> 19:52:17.437455 IP localhost.localdomain.578 > localhost.localdomain.56186: R 0:0(0) ack 3687722494 win 0 19:52:17.440026 IP localhost.localdomain.56186 > localhost.localdomain.482: S 3687722493:3687722493(0) win 3072 <mss 1460> 19:52:17.440252 IP localhost.localdomain.482 > localhost.localdomain.56186: R 0:0(0) ack 3687722494 win 0 19:52:17.442848 IP localhost.localdomain.56186 > localhost.localdomain.94: S 3687722493:3687722493(0) win 3072 <mss 1460> 19:52:17.443016 IP localhost.localdomain.94 > localhost.localdomain.56186: R 0:0(0) ack 3687722494 win 0 3497 packets captured 7000 packets received by filter 5 packets dropped by kernel nmap answers (0.478 seconds and 0.484 seconds) looks very fast for me (7.242 seconds on localhost). Fabrice Dagorn
