I'm trying to scan a bunch of networks with Nmap::Scanner, and it usually works pretty nice. From time to time though I get this error:

<nmap-error>
  <pid="22631"/>
  <cmdline="'/usr/bin/nmap' -v -v -v -v -sP 10.8.179.48/28 -oX -"/>
  <nmap-err>RTTVAR has grown to over 2.3 seconds, decreasing to 2.0
</nmap-msg>
</nmap-error>

[download]

I suspect this is related to the fact that some networks are based on GSM/EDGE, ie very sloooow. The problem is that the scanner breaks the while loop. I want to catch the error, and move on to the next net.

My simplified code:

#!/usr/bin/perl

use warnings;
use strict;
use DBI;
use Nmap::Scanner;

my $sth = $dbh->prepare("Some valid SQL");
$sth->execute();

while(my @r = $sth->fetchrow_array()) {
    print STDERR "Scan network $r[0], mask $r[1]\n";
    my $scanner = new Nmap::Scanner;
    $scanner->max_rtt_timeout(10000);
    $scanner->min_rtt_timeout(1000);
    $scanner->host_timeout(5000);
    $scanner->max_parallelism(8);
    my $results = $scanner->scan("-v -sP $r[0]/$r[1]");
    print STDERR "Scan completed\n";

    my $hsts = $results->get_host_list();
    while(my $host = $hsts->get_next()) {
        # Do stuff for each ...
    }
}

exit 0;

[download]

Any hints on how to solve this is appreciated.

In reply to Nmap::Scanner breaks my while loop, I think by jantelar

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