On Sat, 22 Mar 2008, gv wrote: > hi friends, > i got some error when i try to scan my entire network using nmap > > command is > > # nmap -PN 172.20.0-255.1-254 > netlog.txt. > > every thing seems to be fine up to some time, after scanning a few hosts > nmap generating a error msg like > > RTTVAR has grown to over 2.3 seconds, decreasing to 2.0 > > and no hosts are scanned there after, some days ago it worked fine > > any one has any idea whats going on > > thanks in advance > > -- > gv. >
Hi Venkatesh: The things that can impact are: . slow network . large subnet size RFC 2988 talks about the rules that govern the computation of RTTVAR or round-trip time variation An old thread on nmap-dev discusses this http://seclists.org/nmap-dev/2004/q2/0014.html thanks Saifi.
