Package: nmap Version: 4.62-1 Followup-For: Bug #195299
Hi, since upgrading from etch to lenny(nmap 4.11 to 4.62) I noticed that a script that runs a ping scan across our /16 stopped finding 90% of the hosts. The command ran is simply: nmap --host_timeout 2000 -n -sP -PE a.b.0.0/16 The highest latency on the network is under 100ms, so 2000 should be more than high enough to find everything. I used git bisect against git://git.debian.org/~lamont/nmap.git to track this down to a commit, and the result was d37f15389455ff474c00223cbf18be4117cedd76. The changelog for that says: +o Included David's major massping migration project. The same + underlying engine is now uses for ping scanning as for port + scanning. We hope this will lead to better performance and + accuracy, as well as helping to de-bloat Nmap. Please test it out + and report your results to nmap-dev! For more details, see + http://seclists.org/nmap-dev/2007/q3/0277.html the test I ran was: time sudo nmap --host_timeout 2000 -n -sP -PE a.b.0.0/16 -oG - | grep 'Status: Up' -c I verified that with the previous rev (f501df2e2a74f0bc8ce35a9ddc67d6864afddf96) the results are: num: 3868 time: 9:36 with d37f15389455ff474c00223cbf18be4117cedd76 the results are: num: 291 time: 1:11 so it runs in 1/10th the time, but finds 1/10th the hosts. As a workaround I changed the timeout to 30000. That finds the expected number of hosts, and still runs in about 13 minutes. Unfortunately I'm not sure what the fix for this is :-) It may be working as designed and something just needs to be documented better... -- System Information: Debian Release: 5.0 APT prefers stable APT policy: (500, 'stable') Architecture: i386 (i686) Kernel: Linux 2.6.26-1-686 (SMP w/2 CPU cores) Locale: LANG=en_US, LC_CTYPE=en_US (charmap=ISO-8859-1) Shell: /bin/sh linked to /bin/bash Versions of packages nmap depends on: ii libc6 2.7-18 GNU C Library: Shared libraries ii libgcc1 1:4.3.2-1.1 GCC support library ii libpcap0.8 0.9.8-5 system interface for user-level pa ii libpcre3 7.6-2.1 Perl 5 Compatible Regular Expressi ii libssl0.9.8 0.9.8g-15 SSL shared libraries ii libstdc++6 4.3.2-1.1 The GNU Standard C++ Library v3 nmap recommends no packages. nmap suggests no packages. -- no debconf information -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
