Ping stands for Packet Internet Gopher. Ping basically is the simplest tool to verify network connectivity. We can verify connectivity between any two devices within a private or public network. In simple words, a simple network can be made up of two or more devices connected together using any media and properly configured as well. For example if we connect two computers using Ethernet cable and configured the IP settings properly then we can call it a network. Here ping is the first thing to do to verify the connectivity between two machines within this small network. If network is perfect then both machines A & B will be able to send and receive ping packets between each other. ICMP Protocol: Ping uses ICMP protocol. ICMP stands for Internet Control Message Protocol. Ping basically sends ICMP echo request packet to the destination device and wait for ICMP echo reply from the destination. At the end of its output it shows a statistical summary which contains packets sent and received, packet loss and minimum, maximum and average round-trip time values. The time taken in between sending ICMP echo request and receiving ICMP echo reply is called round-trip time. Ping is not only used for troubleshooting to test connectivity but also it is used to check the response time which determines network latency. First thing ping does is to resolve the...Read More
Author: Saqib Iqbal
User management is one of the most important things to understand before using any operating system. In this tutorial we will talk about user management in Linux and we will focus only on Linux command line interface. This tutorial is designed for beginners and go through most of the stuff a newbie requires without going into too much details. Following topics is going to be covered in this tutorial. Introduction to Linux users & groups System users & normal users in Linux Root user in Linux Show user/group details in Linux User & group configuration files in Linux User creation in Linux Difference between useradd and adduser Set password for user in Linux Create group in Linux Add user to a group in Linux Add user to sudoers in Linux Set user account expiry date in Linux Delete user in Linux Delete group in Linux Introduction to Linux users & groups In Linux, every user has his unique id called user id or UID and at least a member of one group. When a user is created, it’s group with the same name is also created. This group is by default treated as user’s primary group. A user can be a member of two type of groups. The main group which is compulsory and only one group can be a primary group. A secondary group which is optional and...Read More
Take this course
My name is Surendra Kumar Anne. I hail from Vijayawada which is cultural capital of south Indian state of Andhra Pradesh. I am a Linux evangelist who believes in Hard work, A down to earth person, Likes to share knowledge with others, Loves dogs, Likes photography. At present I work at Bank of America as Sr. Analyst Systems and Administration. You can contact me at surendra (@) linuxnix dot com.