Automatically monitoring your home network
The practical Nmap network scanner is used not only by the bad boys in exciting thrillers to detect intrusion targets [1], it also tells admins what devices are actually reachable on their home networks. If you regularly launch Nmap on your subnets and compare the output, you can keep track of newly added or removed devices and proactively ward off nasty surprises.
The fact that nmap has a -oX option that tells it to output the results in XML format is something I was unaware of until I read an Nmap manual that was recently released as a Kindle book [2]. Because an Nmap scan across multiple networks can take a few minutes, I got the idea of building a daemon that finds all the nodes once an hour, keeps the data in memory, and sends it via a built-in web server to requesting clients, such as a Nagios script.
Lean Script Defines the Search Space
The script in Listing 1 [3] does this, mainly by resorting to the NmapServer module (which is loaded in line 7 and discussed later on) and its start() method. Before the call, it defines the IP range of the home network that nmap needs to scan in the constructor – in this case the subnets are 192.168.14.x and 192.168.27.x.
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
US / Canada
UK / Australia
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
CachyOS Now Lets Users Choose Their Shell
Imagine getting the opportunity to select which shell you want during the installation of your favorite Linux distribution. That's now a thing.
-
Wayland 1.24 Released with Fixes and New Features
Wayland continues to move forward, while X11 slowly vanishes into the shadows, and the latest release includes plenty of improvements.
-
Bugs Found in sudo
Two critical flaws allow users to gain access to root privileges.
-
Fedora Continues 32-Bit Support
In a move that should come as a relief to some portions of the Linux community, Fedora will continue supporting 32-bit architecture.
-
Linux Kernel 6.17 Drops bcachefs
After a clash over some late fixes and disagreements between bcachefs's lead developer and Linus Torvalds, bachefs is out.
-
ONLYOFFICE v9 Embraces AI
Like nearly all office suites on the market (except LibreOffice), ONLYOFFICE has decided to go the AI route.
-
Two Local Privilege Escalation Flaws Discovered in Linux
Qualys researchers have discovered two local privilege escalation vulnerabilities that allow hackers to gain root privileges on major Linux distributions.
-
New TUXEDO InfinityBook Pro Powered by AMD Ryzen AI 300
The TUXEDO InfinityBook Pro 14 Gen10 offers serious power that is ready for your business, development, or entertainment needs.
-
LibreOffice Tested as Possible Office 365 Alternative
Another major organization has decided to test the possibility of migrating from Microsoft's Office 365 to LibreOffice.
-
Linux Mint 20 Reaches EOL
With Linux Mint 20 at its end of life, the time has arrived to upgrade to Linux Mint 22.