OTRS is an open source service management solution used by many companies around the world. It's extensibility and ability to integrate with other systems no doubt add to it's popularity. Written in perl, this software will run on mostly anything, and it's low requirement on resources makes it ideal even for a small business to start ticketing, or standardize their internal processes.
In this tutorial we will install OTRS on a Red Hat Enterprise Linux 8. Keep in mind that the steps described below are only apply to version 6.0.14, Community Edition. For example, version 6.0.15 will not work when the below steps are performed on the same environment.
Composer is a dependency management tool for php, much like cpan for perl. If you have read the tutorial about installing cpan, the architecture will be somewhat familiar. Composer, as a command line tool is the client that can fetch and update the php libraries we mark as needed, as well as the libraries these depend on, etc.
The source of these libraries is packagist.org, a large public php package repository. We can browse the repository with a browser to find the packages we'd like to use, then include them in our projects with the help of Composer. And by solving the dependencies itself, Composer can make our lives much easier if we depend on external packages. In turn we can also share our libraries, so the community can access them trough Composer as well.
In this tutorial we will install Composer on Red Hat Enterprise Linux 8, and mark a package as needed dependency for our project, to see the tool working.
Apache Bench is a useful little tool for testing the response time of a webservice, and thus the performance of the webserver. We can specify the number of requests to send, the target URL, set up concurrency, just to name a few of this tool's settings.
While such simulated workloads will not result exactly the same data that real world traffic will do, it is always a good idea to test before going to production. Maybe before deploying a new version of the application, we could run the tests on the new version, and compare the results with the previous test data to see if our application will serve slower, or faster than the last version. With well-planned testing, this tool can show the possible bottlenecks of the application, and may provide points of interest where we should look into our code for possible optimization.
In this tutorial we will install Apache Bench on Red Hat Enterprise Linux 8, as well as an Apache Webserver to run some tests against.
In this tutorial you will learn:
How to install Apache Bench
How to install httpd webserver, and add some basic content
Apache Cassandra is an open-source NoSQL database. One of it's main features is it's decentralized nature that gives unique fault tolerance. Having our data replicated across datacenters means our production will not suffer from the loss of one of our sites, something all sysadmins dream of (or really happy to have such setup).
In this tutorial we will install Cassandra on Red Hat Enterprise Linux 8 by adding the Cassandra repository, install the software, and set up all else needed to have our service up and running and easy to manage.
Apache Kafka is a distributed streaming platform. With it's rich API (Application Programming Interface) set, we can connect mostly anything to Kafka as source of data, and on the other end, we can set up a large number of consumers that will receive the steam of records for processing. Kafka is highly scaleable, and stores the streams of data in a reliable and fault-tolerant way. From the connectivity perspective, Kafka can serve as a bridge between many heterogeneous systems, which in turn can rely on it's capabilities to transfer and persist the data provided.
In this tutorial we will install Apache Kafka on a Red Hat Enterprise Linux 8, create the systemd unit files for ease of management, and test the functionality with the shipped command line tools.
In this tutorial you will learn:
How to install Apache Kafka
How to create systemd services for Kafka and Zookeeper
Gdb or GNU Project Debugger is a great tool when you need to debug a program. You can set breakpoints, watch for value change of a variable, or even change a value for the program while it is halted at a point of it's state, then continue, just to pick some of the features of gdb.
In this tutorial we will install gdb on RHEL 8, and test how it is working with a simple C application.
In this tutorial you will learn:
How to install gdb
How to compile a simple C application with debug symbols
How to set breakpoints in the running application with gdb
How to print actual values of given variables within the application
This article covers an installation of Matomo (Piwik), an all-in-one premium web analytics platform, on RHEL 8 Linux Server. In this instance the installation is based on the well-know LAMP stack comprising the RHEL 8, MariaDB, PHP and Apache webserver.
The NVIDIA Driver is a program needed for your NVIDIA Graphics GPU to function with better performance. It communicates between your Linux operating system, in this case Red Hat Enterprise Linux 8, and your hardware, the NVIDIA Graphics GPU. The NVIDIA drivers can be installed by using the bash command after stopping the GUI and disabling the nouveau driver by modifying the GRUB boot menu.
To install Nvidia driver on other Linux distributions, follow our Nvidia Linux Driver guide.
This tutorial covers step by step installation and configuration of Ansible on Redhat Enterprise Linux 8. Ansible is the leading Open Source configuration management system. It makes it easy for administrators and operations teams to control thousands of servers from central machine without installing agents on them.
There are a ton of ways that you can install RHEL 8 on a virtual machine. This guide will cover using KVM with and without virt-manager as well as VirtualBox.
Red Hat Enterprise Linux version 8.0 has been out for some time and is available for testing purposes on RedHat's website. All you need to do to get it is create an account if you don't already have one, download the ISO and install it using your credentials. If you have previously worked with the 7.x branch of Red Hat Enterprise Linux or CentOS the installation process will be familiar to you since not much has changed.
But what you have to keep in mind is that this is a commercial Linux distribution and thus you will get access not only to technical support but also commercial software, unavailable otherwise in fully open-source Linux distributions based on Red Hat Linux.
In this tutorial you will learn:
How to subscribe to software channels in Red Hat Enterprise Linux 8
How to install software in Red Hat Enterprise Linux 8 with the help of Red Hat repositories
As part of the RHCSA exam preparation, we already learned how to manage partitions on disk. Partitions are useful to separate disk space (for example, separating database-related files from webserver-related files), but we have a much more flexible solution that can separate or aggregate storage space.
This solution is called LVM, the Logical Volume Manager. LVM allows us to see multiple disks as one filesystem, thus overcoming the limitations of a physical disk's site. We can also create software mirroring on disks to protect or data written to the filesystem. In this tutorial we'll cover the basics: we'll manage the three layers of LVM, physical volumes, volume groups and logical volumes.
While in the desktop world we rarely change our hard drive - and that mostly indicated by hardware failure - in the server world it isn't uncommon for the underlying storage environment to change over time.
In a SAN (Storage Area Network) environment, for High Availability, a server can reach it's storage trough many paths, in reality distributed and mirrored to multiple disks in the storage network. If some paths change, the server needs to identify the "disk" again. That's why it is recommended to use special identifiers set on the device, and mount by these identifiers, not by device name which may change. In this part of RHCSA exam preparation tutorial, we'll add a new disk to our test machine, and configure mounting by UUID (Universally Unique IDentifier) and by label.