Re: problem with max retries

[jeetika kataria <jeetika.kataria () gmail com>]

Thank you for you reply. But I have one more question, if I set the scan
delay more than the rtt time out value, will I get the accurate result? How
will Nmap behave on this situation.

On Wed, Nov 16, 2011 at 6:53 PM, David Fifield <david () bamsoftware com>wrote:

> On Wed, Nov 16, 2011 at 01:11:32PM +0100, jeetika kataria wrote:
> > I am doing a UDP port scan with -T4 template but i set the scan delay as
> 5s
> > which is more than rtt timeout, according to this template the max
> retries
> > option is set to 6 but after analyzing the scan it is seen that nmap is
> re
> > transmitting a probe for each port only 2 times rather than 6. Whats the
> > reason for this behavior of Nmap?
>
> Nmap only uses all of its retires when it senses that the network is
> unreliable. The default is --max-retries 10, but it hardly ever sends 10
> retransmissions. Sending a probe only two times is normal behavior. See
> this part of the man page:
>
>        "The default (with no -T template) is to allow ten
>        retransmissions. If a network seems reliable and the target
>        hosts aren't rate limiting, Nmap usually only does one
>        retransmission. So most target scans aren't even affected by
>        dropping --max-retries to a low value such as three."
>
> David Fifield
_______________________________________________
Sent through the nmap-dev mailing list
http://cgi.insecure.org/mailman/listinfo/nmap-dev
Archived at http://seclists.org/nmap-dev/