Nmap is a poplular port scanning program that allows a network to be checked for open ports. It is able to detect open services in a firewall and also the version of the service running on the port such as an Apache web server or Exchange mail server.
The Xmas tree scan turns on the FIN, URG, and PUSH flags, basically an advanced scan that uses different TCP protocol options in an attempt to avoid a firewall or IDS detection of the scan.
The risk from this scan is minimal, from external sources you would often see such scans as they are a part of the "noise" of the internet. Consistent scans from a similar IP source or range may indicate a more targeted fingerprinting of your services, perhaps in preparation for a more dangerous attack.
Connect scan
In linux, issue the following command in the terminal.lsof -i TCP | fgrep LISTENOrdo a port scan using a port scanner like nmapex: nmap In Windows, you can do a port scan to get the list of open ports in your computer. For this use, nmap or zenmap (gui of nmap). There could be other ways but this is the one I have experience on.
To scan a network for DNS servers, you can use a network scanning tool such as Nmap or Fing. Here are the steps to scan for DNS servers using Nmap: Install Nmap on your computer if you haven't already. You can download Nmap from the official website. Open a command prompt or terminal window. Enter the following command: nmap -sU -p 53 --open [IP range] Replace [IP range] with the range of IP addresses you want to scan. For example, if you want to scan all IP addresses on the 192.168.0.x subnet, you would enter nmap -sU -p 53 --open 192.168.0.0/24. Press Enter to run the command. Nmap will scan the specified IP range for open ports on UDP port 53, which is the port used by DNS servers. Once the scan is complete, Nmap will display a list of IP addresses that have an open DNS port. Alternatively, you can use Fing, which is a mobile app that can scan a network for connected devices and display information about them, including their DNS servers. To scan for DNS servers using Fing, follow these steps: Install Fing on your mobile device from the app store. Open the app and tap on the "Devices" tab. Tap on the "Scan" button to scan the network for connected devices. Once the scan is complete, Fing will display a list of devices on the network. Tap on a device to view more information about it, including its IP address and DNS server.
Nmap was created in 1997-09.
Nmap is a poplular port scanning program that allows a network to be checked for open ports. It is able to detect open services in a firewall and also the version of the service running on the port such as an Apache web server or Exchange mail server. The Xmas tree scan turns on the FIN, URG, and PUSH flags, basically an advanced scan that uses different TCP protocol options in an attempt to avoid a firewall or IDS detection of the scan. The risk from this scan is minimal, from external sources you would often see such scans as they are a part of the "noise" of the internet. Consistent scans from a similar IP source or range may indicate a more targeted fingerprinting of your services, perhaps in preparation for a more dangerous attack.
Nmap is a poplular port scanning program that allows a network to be checked for open ports. It is able to detect open services in a firewall and also the version of the service running on the port such as an Apache web server or Exchange mail server. The chistmas tree scan turns on the FIN, URG, and PUSH flags, basically an advanced scan that uses different TCP protocol options in an attempt to avoid a firewall or IDS detection of the scan. The risk from this scan is minimal, from external sources you would often see such scans as they are a part of the "noise" of the internet. Consistent scans from a similar IP source or range may indicate a more targeted fingerprinting of your services, perhaps in preparation for a more dangerous attack.
AnswerUse nmap. See the link in Related Links to go to nmap.
It is for the Nmap Security Scanner.
N comes from National.
Nmap
There are a few ways. Personally, I would use nmap. nmap is a free command-line port-scanner; its an extremely useful and powerful tool, and it is surprisingly easy to use. There are lots of good nmap tutorials: http://www.google.com/search?hl=en&q=nmap+tutorial Or, if you're hardcore about it, I'm sure theres some way of doing this manually using and ARP request, but I'm not really sure how. -DJ Craig
Nmap