Re: [Trisquel-users] How can one capture the "Failed to resolve" output to console during an nMap scan ?

[amenex]

It turns out that nMap doesn't care which way the lookup process goes; I'm  
currently processing the entire file (35,000 lines) for one four-month data  
set, and the hostnames as well as the IPv4 addresses are being handled with  
the same output schemes.

The actual separation process will have to be performed on the "Failed to  
resolve" hostnames in order to extract their IPv4 addresses. The vast  
majority of those have the four octets of the IPv4 address at the beginning  
of the hostname, so my previous explanation will work OK to yield another set  
of unencumbered IPv4
addresses that can be handled easily by the scripts already given. Some of  
those IPv4 addresses will be dead (host not up) or pointing to more than one  
hostname, which made those hostnames unresolvable and therefore easy to  
abuse. The other hostnames in each set of duplicates can be uncovered by  
running nMap on the CIDR block that holds the same server's array of  
hostnames. A few hostnames are duplicated across different CIDR blocks; some  
are even duplicated across different ASN's.