How to create a custom rpm repository on Linux

Rpm is the acronym of RPM Package Manager: it is the low-level package manager in use in all the Red Hat family of distributions, such as Fedora and Red Hat Enterprise Linux.

An rpm package is a package containing software that is meant to be installed using this package management system, and rpm packages are usually distributed via software repositories. In this tutorial we learn how to create a custom rpm repository and how to configure our distribution to use it as a software source.

In this tutorial you will learn:

  • How to create an rpm repository
  • How to use the repository as a software source

Read more

Setting up a MySQL database and user on AlmaLinux

How to install MySQL on AlmaLinux

In this guide, we will show you how to install MySQL on AlmaLinux. There are two separate packages for this on AlmaLinux, depending on what you need to do. You can either install the MySQL client package, which is used to connect to MySQL servers, or install the MySQL server software, which can be used to host your own databases. We’ll cover both below.

After installing a MySQL server, we’ll also go over the first steps you’ll need to get started with hosting a database, which includes making a username and password, creating a database, and granting user permissions on that database. AlmaLinux is a good Linux distro for hosting MySQL, whether you’ve freshly installed AlmaLinux or migrated from CentOS to AlmaLinux.

In this tutorial you will learn:

  • Install MySQL Client on AlmaLinux
  • Install MySQL Server on AlmaLinux
  • How to setup a MySQL database
Setting up a MySQL database and user on AlmaLinux

Setting up a MySQL database and user on AlmaLinux

Read more

Red Hat Enterprise Linux

Oracle Linux vs Red Hat (RHEL)

Oracle Linux and Red Hat Enterprise Linux (RHEL) are well-known Linux distributions, often used in the business world. Each distro has their own pros and cons, differences, and similarities to the other.

In this guide, we’ll be comparing the two distributions across a few key areas and giving a brief review of both distros. Read on to learn more about Oracle Linux and RHEL and how they compare. By the end of this article, you’ll be armed with enough information to choose the best distro for your needs.

In this tutorial you will learn:

  • Oracle Linux and RHEL background information
  • Oracle Linux and RHEL similarities and differences
  • Which distro should I use, Oracle Linux or RHEL?

Read more

Enabling collaboration with setgid directory

Create and configure setgid directories for collaboration – RHCSA Objective Preparation

GNU/Linux filesystem permissions and rights are the basis of the system’s security, and one of it’s principles is the clear separation of rights to files and folders. In a heavily multiuser environment, such as a school’s server, file rights prevent a user by default to accidentally delete or overwrite another’s documents. However, there are use cases where multiple users need to access (read, write, and even delete) other user’s files – such may be the case in the above mentioned school server, where students work on the same project. In this section of RHCSA exam preparation we will learn how to create an environment for such collaboration, using the setgid (set groupID) technique. Note that while we perform these steps on a recent operating system, the setgid isn’t a new thing, and you will find it in any and all distributions.

In this tutorial you will learn:

  • How to add users to a supplementary group
  • How to use set-GID on a directory
  • How to check proper ownership within the set-GID directory
  • How to use the special directory as a member of the group

Read more

Installation of missing php-mbstring on RHEL 7 Linux

The php-mbstring is part of Redhat’s server optional packages. If you have a current subscirption all you need to do is to enable this repository using:

[root@rhel7 ~]# subscription-manager repos --enable=rhel-7-server-optional-rpms

and use yum to install php-mbstring. In case that you do not have a current Redhat subscription you can install php-mbstring directly from IUS project repository:

[root@rhel7 ~]# wget http://dl.iuscommunity.org/pub/ius/stable/Redhat/7/x86_64/ius-release-1.0-13.ius.el7.noarch.rpm
[root@rhel7 ~]# wget http://dl.fedoraproject.org/pub/epel/7/x86_64/e/epel-release-7-2.noarch.rpm
[root@rhel7 ~]# rpm -Uvh *release*.rpm

Read more

SSH login to RHEL 7 server without password

In order to login to RHEL7 Linux server we first need to exchange public keys between server and client machine. To do that we can use ssh-copy-id command.

$ ssh-copy-id user@rhel-server
The authenticity of host 'rhel-server (rhel-server)' can't be established.
ECDSA key fingerprint is 21:4d:71:f6:ef:1f:c1:f7:a9:d9:81:4d:9d:34:4d:a9.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
user@rhel-server's password: 

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'user@rhel-server'"
and check to make sure that only the key(s) you wanted were added.

Read more

Mount and install VirtualBox Guest Additions on Redhat 7 linux

RHEL 7 VirtualBox Guest Additions installation

In this short tutorial we will show you how to install VirtualBox Guest Additions on RHEL 7 gnome desktop. To start simply boot to virtual RHEL 7 system. First we will install all prerequisites. To do that open terminal and enter following linux commands:

[root@rhel7 ~]# yum groupinstall 'Development Tools'

as well as we will need kernel development package:

[root@rhel7 ~]# yum install kernel-devel

Read more

Redhat 7 boot screen - enter vnc and network options

Initiate Redhat installation remotely via VNC

Apart of the regular local Redhat’s installation, the Redhat system allows admin to modify boot options to temporarily setup network interface and instruct the installation program Anaconda to initiate installation via VNC. In this article we will modify default Redhat’s boot options to initiate remote installation using VNC.

First insert installation image and boot into a Redhat’s boot options screen as show below:

Redhat 7 boot screen - enter vnc and network options

On this screen we need to modify boot options to instruct the installation program Anaconda to provide us with VNC interface after the end of the boot sequence. Depending whether you use DHCP on your network you can either set static address or do not include any network options for dynamic IP address assignment. In the above screen we have included the following options after pressing “TAB” on the main ( first ) boot option:

ip= - optional
netmask= - optional
vnc - required

Read more

Red Hat Enterprise Linux running GNOME desktop environment

Red Hat Linux Download

Red Hat Enterprise Linux is a commercial Linux distribution built for powering the servers of corporations and data centers. It’s a robust distro with the features and stability that businesses crave for high availability and predictability.

The big appeal of Red Hat, though, is its support system. That’s the main thing you’re paying for, after all. If something doesn’t operate as expected, businesses want someone to turn to for support so they can face as little downtime as possible. Red Hat experts are only a phone call away for subscribers.

The support feature is what really sets Red Hat apart from other Linux distributions that could also perform the same job very well, such as CentOS, Fedora, and OpenSUSE. For other most popular Linux distributions please visit our dedicated linux download page.

Red Hat offers training and certification programs to prospective Linux system administrators. This is another big plus for businesses, as they can buy training for their employees or vet new recruits by their certifications. Such training and certifications are rare to find in the Linux world, being that Linux distros are mostly free and run by a community of volunteers.

If you are a system administrator looking to get into Red Hat, most or all of your experience with CentOS and Fedora Server should transfer over to Red Hat, since the three distributions are closely related.

Read more

Adding swap space to the system

Add new partitions, logical volumes, and swap to a system non-destructively – RHCSA Objective Preparation

Disk and space management is an essential knowledge of a sysadmin. It is his or her everyday job to handle disk issues. As part of the RHCSA exam preparation, we will learn how to add new space of various types to the system, using the tools provided by RHEL8. We already covered many of these tasks, and in this tutorial we will focus on adding new space without harming the data contained in the system.

In this tutorial you will learn:

  • How to add new partitions to RHEL8
  • How to add new logical volumes to RHEL8
  • How to add swap to RHEL8

Read more