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Questions tagged [nmap]

Nmap (Network Mapper) is a security scanner originally written by Gordon Lyon (also known by his pseudonym Fyodor Vaskovich) used to discover hosts and services on a computer network, thus creating a "map" of the network.

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Command line tools for ping HTTP?

Background : It's a common question as we can search at google "ping works but http does not" ping is not a reliable test of network connectivity. ping working just means enough of the IP stack is up to process ICMP Echo requests (that's not a huge…
Md Mahbubur Rahman
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Nmap ping scan over a VPN tunnel return all hosts alive?

I'm curious as to why running an nmap -sP (ping scan) on a remote subnet linked via a Cisco site-to-site IPSec tunnel returns "host up" status for every IP in the range. [root@xt ~]# nmap -sP 192.168.108.* Starting Nmap 4.11 (…
ewwhite
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Is there a Nagios plugin that uses Nmap and does port checking?

I need to monitor open and closed ports on dozens of hosts. I've found a Nagios plugin that does what I need, but I would have to use this script through NRPE. Some of the hosts are powered by Linux and they all have Perl installed. But some of them…
Eedoh
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Best way to determine if IPs in a subnet are up or down in Linux

I have a simple method that I am using on four subnets to determine which registered IPs are actually up and active, and which ones can be removed. Initially, I iterate through the list of domain names with this command: sudo nmap -sS -O -v oN…
UnworthyToast
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NMAP (or other) continuous port scan until it returns open?

Is there a way with nmap or anything else to do a continuous port scan, say on port 22, until the service comes up and the port is coming back as open? Kind of like you may have an infinite ping going, timing out, to see when a host comes back…
TryTryAgain
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Completely getting rid of SSLv3 on Apache

Our security team is asking that we completely disable SSLv3 on some of our servers running Apache. I've used the SSLProtocol entry in the ssl.conf file (like SSLProtocol ALL -SSLv2 -SSLv3) and various SSLCipherSuite entries to try to disable this…
Stefan
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nmap and arp-scan inconsistent IP-MAC results

I seem to get variable and inconsistent results for the IP/MAC addresses from a particular machine, using nmap or arp-scan. The machine has 3 interfaces, and this is what it shows: $ uname -a Linux showstore-81 2.6.35.13 #1 SMP PREEMPT Thu Feb 9…
mivk
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Scan for connected, powered on computers on a network?

I want to scan for powered on computers on my LAN and gather logs about that. I tried nmap but it didn't work very well (a lot of switched on computers are not getting detected). nmap -sP 192.168.2.0/24 Nmap done: 256 IP addresses (10 hosts up)…
Jorge Suárez de Lis
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Using nmap to scan open ports. iptables default policy affects other rules?

I'm trying to find out why changing my default iptables policy is affecting what nmap sees when it scans my host. Consider the following iptables setup: iptables -F iptables -A INPUT -p tcp -s 10.1.0.0/20 --dport 22 -j ACCEPT iptables -P INPUT…
Ation
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Automatic/scheduled check for open ports on list of servers

I need a way to configure a scheduled check for open ports on a list of servers and to get notified if something has changed from last check. what's the best way to do it? If there is some solution which talk with Nagios it would be even better.
SecondThought
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Fast ARP scan in address-less DAD (Duplicate Address Discovery) mode

I am developing system for detecting network actual state. One part is to get all IPs and their respective MAC addresses. Right now I am using arping in DAD (Duplicate Address Discovery) mode. I send arping for every possible IP in the ranges that…
Radek Hladík
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Removing new fingerprint detection message from nmap

I run a nmap scan of my hosts daily to check for open ports. sudo nmap -f -sS -sV --log-errors -append-output -p1-9999 host.com But along with the output I get a long list of fingerprint submissions for unrecognized ports like this…
Quintin Par
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nmap reports host up when it isn't

On an Ubuntu VMWare VM I ran: sudo nmap -sP 192.168.0.* This returned: Starting Nmap 5.00 ( http://nmap.org ) at 2010-12-28 22:46 PST Host 192.168.0.0 is up (0.00064s latency). Host 192.168.0.1 is up (0.00078s latency). Host 192.168.0.2 is up…
martianway
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Why do nmap -p and nmap -A scans show different results?

I have a C# application that I've written that listens on port 789. It is running on a Windows XP Professional computer. Running netstat -an | find "789" TCP 0.0.0.0:789 0.0.0.0:0 LISTENING When I run nmap -A -vv ip on…
Andrew
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Finding XP boxes on our intranet

We're out on a mission to find and eradicate XP boxes on our intranet. Now we're wondering what the fastest (scan) method might be --XP boxes connected to our active directory have already been identified, but now we need to find the remaining,…
Ralf Hildebrandt
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