Configure Static IP Addresses on Ubuntu 18.04 Server - Step by Step Process ?

This article covers method to set up a static IP address on Ubuntu 20.04. Basically, in most network configurations, the IP address is assigned dynamically by the router DHCP server. 

The recommended way to assign a static IP address to a device on your LAN is to configure a Static DHCP on your router. Static DHCP or DHCP reservation is a feature found on most routers which makes the DHCP server to automatically assign the same IP address to a specific network device, each time the device requests an address from the DHCP server. This works by assigning a static IP to the device's unique MAC address.

To Get the name of network interface and the default gateway in Linux:

You can either use ip command or the network manager CLI like this:

$ nmcli d

Configure Network in Linux Using Netplan and NMTUI - Step by Step Process ?

This article covers how to set up your network interface using Netplan and NMTUI. Setting up the network interfaces is one of the most basic step that every system administrator and server engineers have to do to make it accessible over the network.

Netplan is based on YAML based configuration system that makes configuration process very simple. Netplan has replaced the old configuration file /etc/network/interfaces that we previously used for configuring network interfaces in Ubuntu.

To Restart the network service

1. Once all the configurations are successfully applied, restart the Network-Manager service by running the following command:

$ sudo systemctl restart network-manager

2. If you are using a Ubuntu Server, instead use the following command:

$sudo systemctl restart system-networkd

To Verify IP address

Now to verify if the new configurations are successfully applied, run the following command to verify the IP address:

$ ip a

The Netplan default configuration file is under the directory /etc/netplan

You can find that using the following command:

$ ls /etc/netplan/

To view the content of Netplan network configuration file, run the following command:

$ cat /etc/netplan/*.yaml

Use the Who Command in Debian 10 - How to do it ?

This article covers the who command in Linux along with its some of the useful command line options.

Sometimes, while working on the command line, you might want to know more about logged in users.

There exists a command line utility who which you can use to access this kind of information.

Basically, the who command shows who all are logged in.

Here's its syntax:

$ who [OPTION]... [ FILE | ARG1 ARG2 ]

To access time of last system boot?

For this, use the -b command line option:

$ who -b

Find UUID in Linux Mint 20 - How to do it ?

This article covers the different methods to find out the UUID in a Linux Mint 20 system.
UUID is the "universally unique identifier" that is assigned to devices on a Linux system for the purpose of identification.
For example if your hard disk has 3 partitions then each partition is a device and has a uuid.
Similarly cd/dvd, usb drives etc all are assigned a uuid.

Different methods To identify Disk Partition/FileSystem UUID in Linux:
1. blkid Command: locate/print block device attributes.
2. lsblk Command: lsblk lists information about all available or the specified block devices.
3. hwinfo Command:  hwinfo stands for hardware information tool and great utility that used to probe for the hardware present in the system.
4. udevadm Command: udev management tool.
5. tune2fs Command: adjust tunable filesystem parameters on ext2/ext3/ext4 filesystems.
6. dumpe2fs Command: dump ext2/ext3/ext4 filesystem information.
7. Using by-uuid Path: The directory contains UUID and real block device files, UUIDs were symlink with real block device files.

Monitor Network Traffic with vnStat on Ubuntu 20.04 - How to do it ?

This article covers how to install and use this tool on Ubuntu 20.04 LTS for monitoring the traffic on network interfaces.

vnStat is a handy tool to keep an eye on the bandwidth usage on your Linux OS.

To Install vnstat using the apt/apt-get on Ubuntu:

1. Type the following apt command/apt-get command to update the system:

$ sudo apt update
$ sudo apt upgrade

2. Search for vnstat package, enter:

$ apt show vnstat

3. Execute the following command to set up and install vnstat on Ubuntu server:

$ sudo apt-get install vnstat


$ sudo apt install vnstat

To Enable and start the vnstat service on Ubuntu:

Run the command below:

$ sudo systemctl enable vnstat.service

To Start the vnstat service

$ sudo systemctl start vnstat.service

To Stop the vnstat service

$ sudo systemctl stop vnstat.service

To Restart/reload the vnstat service

After editing the /etc/vnstat.conf, we must restart or reload the service:

$ sudo systemctl restart vnstat.service


$ sudo systemctl reload vnstat.service

To Find the status of vnstat service

$ sudo systemctl status vnstat.service

View Standard Log Files on Ubuntu Linux Servers - How to do it ?

This article covers how to view standard log files for troubleshooting any Linux system. Linux system administrators often need to look at log files for troubleshooting purposes.

Linux and the applications that run on it can generate all different types of messages, which are recorded in various log files. Linux uses a set of configuration files, directories, programs, commands and daemons to create, store and recycle these log messages. 

Knowing where the system keeps its log files and how to make use of related commands can therefore help save valuable time during troubleshooting.

To view log files on Linux:

Open the Terminal or login as root user using ssh command. 

Go to /var/log directory using the following cd command:

# cd /var/log

To list files use the following ls command:

# ls

To Configure Log Files on Ubuntu and CentOS:

This section explains different mechanisms for configuring log files. Let's start with a CentOS example.

To view users currently logged onto a Linux server, enter the who command as a root user:

$ who

This also lists the login history of users. 

To view the login history of the system administrator, enter the following command:

$ last reboot

To view information of the last login, enter:

$ lastlog

To Execute Log Rotation on Linux:

Log files that have zeroes appended at the end are rotated files. That means log file names have automatically been changed within the system.

The purpose of log rotation is to compress outdated logs that are taking up space. Log rotation can be done using the logrotate command. This command rotates, compresses, and mails system logs.

logrotate handles systems that create significant amounts of log files. The command is used by the cron scheduler and reads the logrotate configuration file /etc/logrotate.conf. It's also used to read files in the logrotate configuration directory.

Setup Git Server on Ubuntu 20.04 - Step by Step process ?

This article covers how to install and configure a Git server on Ubuntu. Git is basically a Version control system which allows you to keep track of your software at the source level. With Git, You can easily track changes, revert to previous stages, and branch to create alternate versions of files and directories.

To install Git on Ubuntu Server:

1. Run the following commands as sudo user:

$ sudo apt update && sudo apt install git

2. To install the git package on CentOS servers type:

$ sudo yum install git

3. Next, create a new user that will manage the Git repositories:

$ sudo useradd -r -m -U -d /home/git -s /bin/bash git

The user home directory is set to /home/git

All the repositories will be stored under this directory.

Assign Multiple IP Addresses to Single NIC in Linux Mint 20 - How to Do it ?

This article covers how to assign multiple IP addresses to a single interface in Mint OS. By following our guide carefully, you can either assign the IP address temporarily or permanently to your network interface.

NIC stands for network interface controller or network interface (controller) card. WNIC is wireless network interface controller or wireless network interface (controller) card. IP Addresses belong to network interfaces, not to the computer itself.

To Restart network service using command:

# systemctl restart network

To Verify the new IP address using command:

# ip addr

How configure multiple IP address in CentOS ?

Now, in order to add additional IP addresses you'll need to edit the configuration file (from hereon called “config file”) for this specific interface. On CentOS 7, the interface config files are located in /etc/sysconfig/network-scripts/ and they are all prefixed with ifcfg-.

How remove secondary IP address Linux?

To add or remove additional IP adresses and keep the configuration persistent, we need to Edit the corresponding /etc/sysconfig/network-scripts/ifcfg-eth[x] configuration file and add/remove as many additional IPADDR[n] and PREFIX[n] entries as additional IP addresses are required.

To configure a static IP address on CentOS  / RHEL :

1. Create a file named /etc/sysconfig/network-scripts/ifcfg-eth0 as follows:






2. Restart network service: systemctl restart network.

How do I login as a different user in Linux?

To change to a different user and create a session as if the other user had logged in from a command prompt, type "su -" followed by a space and the target user's username. Type the target user's password when prompted.

What is Nmcli in Linux?

nmcli is a command-line tool which is used for controlling NetworkManager. nmcli commnad can also be used to display network device status, create, edit, activate/deactivate, and delete network connections. Typical Uses: Scripts: Instead of manually managing the network connections it utilize NetworkMaager via nmcli.

Difference between the output of ifconfig and ipconfig:

Functionality: The ipconfig command displays all the currently connected network interfaces whether they are active or not. 

On the other hand, the ifconfig command displays only the enabled network interfaces that are connected to the system.

Configure Static IP in Debian 10 - Step by step process to do it ?

This article will guide you on the how to set up a static IP configuration in #Debian 10. Using either the command line or #GUI method, you can easily configure the static IP address on your system.

The ifconfig utility is used to change the IP address of a network interface.

To change your #IP address on #Linux, use the “ifconfig” command followed by the name of your network interface and the new IP address to be changed on your computer. 

To assign the subnet #mask, you can either add a “netmask” clause followed by the subnet mask or use the CIDR notation directly.

To Configure static IP address on Ubuntu 16.04 LTS Server:

1. Edit the /network/interfaces file. sudo nano /etc/network/interfaces.

2. Restart the networking service (or reboot) Once you are confident the change has been made, and if you don't want to reboot you can just restart the networking service.

To Display Available Network Interfaces in Linux:

i. ip #command – It is used to show or manipulate routing, devices, policy routing and tunnels.

ii. #netstat command – It is used to display network connections, routing tables, interface statistics, masquerade connections, and multicast memberships.

iii. #ifconfig command – It is used to display or configure a network interface.

Step by step process to install and configure HAproxy on Ubuntu 20.04 LTS ?

This article will guide you on how to #install and configure #HAproxy load balancer on the #Linux system. 

You will learn the basic setup and configuration of HAproxy as a load balancer for #Apache web servers. Also, we looked at some commands for managing the HAproxy server. In the end, we tested the load balancing through the browser and the #curl command. 

HAProxy is free, open source #software that provides a high availability #load #balancer and proxy server for #TCP and HTTP-based applications that spreads requests across multiple servers.

To Deploy on Linux :

1. Download the source code of HAProxy.

2. Unzip the file into the desired location tar xvzf haproxy-1.8-dev1.

3. Compile the source code.

4. Create config file haproxy.cfg with the configuration details.

5. Start the haproxy with ./haproxy -f haproxy.

6. Access the status page on http:localhost:9999/stats.

Step by step process to install Zimbra on Ubuntu 18.04 LTS ?

This article will guide you on how to #install Zimbra on Ubuntu. Zimbra is an open-source #mail server that offers several features. It is recommended to install it in a #machine that has enough memory, processor, and disk space available. 

To install and configure #Zimbra mail server:

1. Install System Packages.

2. Configure System #Hostname.

3. Add a Static IP Address.

4. Disable Unwanted Services.

5. Install Zimbra Collaboration Suite Open Source Edition.

6. Zimba Initial Configuration.

Steps to restart network services in Linux ?

This article will guide you on how to start, stop, and restart the #network service on different Linux distribution like Ubuntu, #Debian, Linux Mint, and CentOS 8. Moreover, you can troubleshoot the network #error through the #NetworkManager tool on #CentOS 8.

Please don't stop services if you have a remote ssh connection that may create a problem.

Restarting networking on a desktop machine will cause dbus and a bunch of #service to stop and never be started again, usually leading to the whole system being unusable.

To restart a Linux service:

1. Linux provides fine-grained control over system services through #systemd, using the systemctl command.

2. To verify whether a service is active or not, run this command: sudo systemctl status apache2.

3. To stop and restart the service in Linux, use the command: sudo systemctl restart SERVICE_NAME.

How to import a OpenVPN .ovpn file with Network Manager or Command Line in Linux

This article will guide you on how to import .opvn (OpenVPN config) file using a GUI or CLI method in Linux.

A complete guide on how to run two or multiple networks instance of Tinc VPN on same box

This article will guide you on how to use Tinc to create a mesh network of two different VPN on the same server.

Learn how to set up NFS Server of CentOS 8 and RHEL 8

This article will show you how to install and configure an NFS Server on CentOS 8 Machine, Our Server Experts will take you through the steps to create files on both the NFS Server and Client and enable you share files efficiently between two or more systems.

How to configure DNS Server on CentOS 8?

Here, you will learn how to install and configure a DNS Server on CentOS 8 machine.

A complete guide on how to set up Static IP address on CentOS 8

This article will guide you on how to configure a Static IP address on CentOS 8.

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