Category Archives: Networking

Tcpdump usage examples

Posted on June 7, 2016 by paradox

In most cases you will need root permission to be able to capture packets on an interface. Using tcpdump (with root) to capture the packets and saving them to a file to analyze with Wireshark (using a regular account) is … Continue reading →

Posted in Linux How-To, Networking, News and Security, Windows How-To | Leave a comment

USB Rubber Ducky | USB Rubber Ducky

Posted on August 19, 2015 by paradox

I want one of these 🙂

Posted in Networking, News and Security | Leave a comment

Hak5 – Building a high performance home router

Posted on July 17, 2015 by paradox

This was a pretty cool setup.

Posted in Networking | Leave a comment

Setting Up a FreeBSD Router, Step-by-Step

Posted on May 19, 2015 by paradox

HARDWARE INFO: rl0 – NIC facing the 192.168.0.0 network xl0 – NIC facing the 192.168.1.0 network xl1 – NIC facing the modem tun0 – The virtual NIC used by PPP, facing the outside SECTION 1: PRELIMINARY SETUP Install FreeBSD Enable … Continue reading →

Posted in Linux How-To, Networking | Leave a comment

Nagios NRPE example setup

Posted on May 19, 2015 by paradox

Ubuntu #> apt-get install nagios-nrpe-server nagios-nrpe-plugin CentOS and Fedora #> yum install nrpe nagios-plugins-load nagios-plugins-users nagios-plugins-swap nagios-plugins-disk #> chkconfig –add nrpe FreeBSD #> cd /usr/ports/net-mgmt/nrpe* #> make #> make install clean #> In /etc/nagios/nrpe.cfg Set the following dont_blame_nrpe=1 (default set … Continue reading →

Posted in Linux How-To, Networking | Leave a comment

Block Port 25 with IPTables

Posted on May 19, 2015 by paradox

Block all port 25 except from localhost -A INPUT -p tcp -s localhost –dport 25 -j ACCEPT -A INPUT -p tcp –dport 25 -j DROP

Posted in Linux How-To, Networking | Leave a comment

Subnet Mask Cheat Sheet

Posted on May 19, 2015 by paradox

Addresses Hosts Netmask Amount of a Class C /30 4 2 255.255.255.252 1/64 /29 8 6 255.255.255.248 1/32 /28 16 14 255.255.255.240 1/16 /27 32 30 255.255.255.224 1/8 /26 64 62 255.255.255.192 1/4 /25 128 126 255.255.255.128 1/2 /24 256 … Continue reading →

Posted in Networking | Leave a comment