Beginner's Guide to Nmap Ever wondered how attackers know what ports are open on a system? Or how to find out what services a computer is running without just asking the site admin? You can do all this and more with a handy little tool called Nmap. What is Nmap? Short for "network mapper," nmap is a veritable toolshed of functionality to perform network scans. It's famous, too. In this tutorial, I'll cover some of the basics of using Nmap and provide some examples you can use quickly. Getting Nmap and Basic Use You'll find Nmap packaged for most major Linux distros. The basic syntax for Nmap is Nmap Scan Type Options target. nmap -O target.host.com Note that Nmap requires root privileges to run this type of scan. Starting Nmap 5.21 ( ) at 2010-02-27 23:52 EST Nmap scan report for 10.0.0.1 Host is up (0.0015s latency). As you can see, Nmap provides a lot of data. Here's the result of another scan, against a desktop machine running Ubuntu 9.10: Practice Hosts Multiple Hosts Checking Open Ports Zenmap
Vmyths.com 10 Free Server & Network Monitoring Tools that Kick Ass By Ben Dowling When you have a website or a network, it’s helpful to be aware of any issues as soon as they occur. There are open source and freeware server/network monitoring tools that will supervise your infrastructure for any issues that may arise. These tools are meant to aid you in avoiding being taken offline and evaluating if your resource needs has outgrown your infrastructure. In this article, we review our top 10 server/network monitoring tools. You will see a variety of server applications here so that you might find the tool (or tools) for your needs. 1. Monit not only monitors your server, but also attempts to remedy problems by taking predefined actions for certain situations. If you have more than one server that you need to monitor, then you can use M/Monit– an extended version of Monit that provides a simple way to monitor multiple machines. 2. When you have a cluster of machines, it’s difficult to see how the whole cluster is doing all at once. 3. 4. 5. 6. 7. 8. 9. 10.
10 Cool Ways to Use Nmap Nmap (“Network Mapper”) is a free and open source (license) utility for network exploration or security auditing. Many systems and network administrators also find it useful for tasks such as network inventory, managing service upgrade schedules, and monitoring host or service uptime. In addition to my list you can also check out this Comprehensive Guide to Nmap here and of course the man pages Here are some really cool scanning techniques using Nmap 1) Get info about remote host ports and OS detection nmap -sS -P0 -sV -O <target> Where < target > may be a single IP, a hostname or a subnet -sS TCP SYN scanning (also known as half-open, or stealth scanning) -P0 option allows you to switch off ICMP pings. -sV option enables version detection -O flag attempt to identify the remote operating system Other option: -A option enables both OS fingerprinting and version detection -v use -v twice for more verbosity. nmap -sS -P0 -A -v < target > 2) Get list of servers with a specific port open