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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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nmap find all alive hostnames and IPs in LAN

How can I issue a nmap command that shows me all the alive machines' IP addresses and corresponding hostname s in the LAN that I am connected? (if this can be done in another way/tool you surely are welcome to answer)
şaloma
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NMAP: Check if port 80 and 8080 is open

In our company, I want to check if users are running web servers on port 80 and 8080. I downloaded nmap and ran this command: nmap -p 80,8080 192.168.1.0-255 I got a list of IPs and tried to access them in my browser (EG: 192.168.1.1:8080) but…
Ian
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Displaying nmap result gradually as results are found

To get nmap results, one has to wait for the end of the scan. How can I force nmap to gradually display the newly found hosts and open ports while it is running?
user123456
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Nmap: find free IPs from the range

Is there a way to scan for free IPs on the network? I use nmap -sP 192.168.1.0/24 but this actually shows hosts that are up.
HTF
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Check if remote host/port is open - Can't use GNU Netcat nor NMap - RHEL 7

At work, the infrastructure team is rolling out new VMs with RHEL7 installed as the base OS. This particular image comes with the nmap-ncat version of Netcat and does not have NMap installed. We are precluded from installing anything on the…
λ Jonas Gorauskas
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Nmap not scanning all ports

I've noticed that nmap only scans a bunch of known ports, and the only way i've managed to check 'em all is to put a "-p 0-65535" in. Why is that? am I wrong? is there a more popular way to scan all ports aside from what I've done?
SecondThought
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nmap does not find alive hosts with ping scan

I try to ping scan my local network using nmap, but it doesn't seem to find machines that are for sure alive. It responses to ping but on to ping scan. Results for ping: $ ping 192.168.0.2 PING 192.168.0.2 (192.168.0.2): 56 data bytes 64 bytes from…
aadam
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Is there a way to see what is actually filtering TCP port communication?

nmap -p 7000-7020 10.1.1.1 Will output all the filtered ports Starting Nmap 6.40 ( http://nmap.org ) at 2015-03-04 12:18 EET Nmap scan report for 10.1.1.1 Host is up (0.00091s latency). PORT STATE SERVICE 7000/tcp filtered…
Eduard Florinescu
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Can I use nmap to discover IPs and mac addresses?

When I need to locate the IPs of devices by their mac address on a Windows system, I normally use Advanced IP Scanner (from radmin.com) to scan the network, then I use arp -a to list the mac addresses. Is it possible to use nmap to perform the same…
vfclists
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command for MAC broadcast

I am looking for a command to discover all hosts on the same LAN segment from a host with unassigned IP, default gateway, and subnet. I know there's ping 255.255.255.255 but that operates at layer 3 and requires the sender have an IP address. Is…
T. Webster
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IMAP connection with Dovecot keeps failing (time-out)

* TLDR ; if you have connection problems, not only make sure you have added the required rules to your firewall, but also make sure ($ iptables -L -v) that the rules are in the correct order! * It's been a few days now, and I can't figure out why…
TomDogg
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Test if an IP is being used in an internal network without using nmap

I can perform port scan using nmap to test if a given IP is being used, e.g. nmap -PR 192.168.1.9 However, nmap is not installed in most server, is it possible to have the same result (e.g. check if the particular IP is being used) without…
Ryan
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How to check if an IP address is free on a network

I'm gonna setup a Wireless router for a customer. They have subnet 10.253.48.0/24 What can I do to check if the IP 10.253.48.243 is available to set up the router? I'm on out on a local network at my workplace, the customer's network is IPVPN. I…
IT-Arkitekt
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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…
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