Category: Tutorials

How to check if DNS is working

This article understands how to check if your DNS is actually working or not. DNS is used for resolving the domain name into IP address. In the below topology, the PC is connected to a router, which is connected to the internet. The PC has received appropriate IP …

Top Skills for Network Engineers

This article lists the top skills for network engineers. 1. TCP/IP TCP/IP is a must have skill for network engineers. In today’s distributed network environment, components from different vendors would be used. TCP/IP is the common protocol suite which would be used for inter networking. Network Engineers should …

Python IP Scanner

The Python IP scanner is a command line tool which takes the IP addresses to be scanned on the network. The tool displays the IP addresses which are shutdown and up. The final count is displayed based on the number of systems which are up and running on …

Python Scapy tutorial

This tutorial shows how to send a icmp ping packet with Python and Scapy. The tool which is named as L3 troubleshooting tool sends a ping packet to the destination and prints the response. The 1st step is to create a python file using the command vi l3tshoot.py …

Wireshark tutorial

This wireshark tutorial for beginners understands the different types of filters which can be used for various conditions. The list of conditions are appropriate filters are explained. How to monitor Ethernet packets with a specific source address. In this scenario, all ethernet packets which are originating from a …

How to measure packet loss

This tutorial explains how to measure packet loss from a Windows system. The test can be used to measure packet losses on any network. Ping is a tool , which would analyze if a remote system is up or down. On Windows , ping can be customized to …

Wireshark examples

This tutorial contains wireshark examples for various scenarios. Wireshark filter to display all packets originating from a specific source address. The filter displays all packets which has the source IP address in the IP header as 192.168.100.10     Wireshark filter to display TCP reset connections on a …

How to use Python with netstat

This tutorial explains how we can combine netstat with Python for automation. Install Python on the system and create a file Pythonnetstat.py. Type the following code. import os a=os.popen(‘netstat -a’).read() print ” \n Connections “,a Take our Python Network programming Course for $12.99 on udemy The first line …

TCL essentials for network automation

Variable initialization To initialize a variable the set command is used. For ex, to assign the variable i with the value 3, set i 3 is used.   Incrementing values To increment the value of the above variable i, the command incr i is used. Printing values The …

scapy examples

The following lists scapy examples based on experiments performed on the below topology. The topology contains two PC’s , Ubuntu and Windows 7. Scapy is setup on Ubuntu system. Example 1 – How to send a ping packet from Scapy on Ubuntu to Windows 7. ip=IP() # Creates …