Linux System Engineer

Linux is an open source operating system, launched in 1991 for computers, but its use has expanded to support systems for cars, phones, web servers and, more recently, networking equipment.

Its longevity, maturity and security make it one of the most reliable operating systems available today, which means that it is ideal for commercial network devices, as well as for companies that want to use it and its peripherals to customize their own network infrastructure and data centers.

This in turn makes GNU / Linux System Engineer skills highly sought after by IT hiring managers. Many of the new technologies associated with DevOps, for example, containers, OpenSource infrastructure and SDN controllers are based on GNU / Linux.

So what is GNU / Linux?
GNU / Linux, an operating system similar to Unix, is distributed under open source licenses, which means that the following rules apply that make it attractive to businesses:

GNU / Linux operating system is free to run.
Administrators can study the operating system and customize it for specific purposes.
Unlimited redistribution privileges of the original or modified versions of the operating system.


The GNU / Linux operating system consists of the following components:

Kernel This is the core of the system and sends instructions to the CPU, peripherals and memory.
Bootloader. The processes that manage system startup. On a computer the user would recognize this by the welcome screen. On a network device there is a status that indicates the boot process.
Daemons Background services that begin at boot time or after the system is fully active. For example, the network daemon activates all network interfaces during startup. Other daemons are things like time and DNS.
Shell. This is the GNU / Linux command line. It can be intimidating for people who are used to working in graphic environments, but most network professionals are used to operating in a shell.
In addition to the shell, GNU / Linux servers also have a graphical desktop environment and applications that run on top of it. There are some network applications for GNU / Linux, such as traffic analysis, security and network administration, which also have graphical interfaces, but are much less in number than those of servers and desktops.

GNU / Linux in the kernel
Actually, the command line interfaces (CLI) that most network administrators use today to configure routers and switches of their favorite network provider are highly customized versions of GNU / Linux with provider-specific interfaces that run over of them. The challenge with this is that the skills needed to work with them are not very portable from seller to seller. A very competent engineer who works with Cisco IOS probably could not work with Junos de Juniper because each one includes its own different abstraction layer that is above the pure GNU / Linux code.

GNU / Linux itself, instead of working through an abstraction layer, provides direct access to routing and forwarding tables, notification systems, telemetry information and different interfaces. That can make GNU / Linux more flexible, and with the support of the large GNU / Linux community, potentially faster to respond to the need for new services that a commercial provider could be.

You should not worry that a GNU / Linux-based platform is a "minor" device. GNU / Linux has an excellent ecosystem with mature APIs, as well as an agile network stack optimized for the modernized data center. For example, GNU / Linux is designed with a separate control and data forwarding plans that facilitate the fall in software-defined network architectures, because the separation of those planes is the basis of SDN.

Another element that GNU / Linux-based products can contribute to the network is that switches can be managed with policy-based automation and open source orchestration tools such as Ansible, Puppet and Chef. There are approximately 25 of these tools available with support for different Unix flavors but all of them also support GNU / Linux.
GNU / Linux based products

In the last decade there has been an explosion in the number of GNU / Linux based products that have had a great impact on the IT space, including:

Kubernetes: Google Container Cluster Administrator.
OpenStack: Software platform for infrastructure such as cloud service platforms.
Open Daylight: the Java-based project of the GNU / Linux Foundation to accelerate the adoption of SDNs and Network Functions Virtualization (NFV)
Docker: Software container program
Open vSwitch (OVS): Distributed multilayer virtual switch to provide a switching stack within virtualization environments. OVS in particular is interesting because it offers a richer set of network features than the core capabilities of the GNU / Linux kernel. If OVS is even moderately successful, it could be an excellent precursor to the way things come in networking.
Having the ability to manage, configure and troubleshoot GNU / Linux networks is increasingly necessary if organizations want to take advantage of any of these projects in production environments.

GNU / Linux is undoubtedly increasingly widely adopted in all areas of technology. Networking has taken a long time to embrace GNU / Linux, but the more they depend on the network, the more network and server domains merge. For network engineers, being able to access the native GNU / Linux shell allows them to use tools and software that were once available only to servers. This greatly facilitates the orchestration of network services with changes in servers and applications.

In addition, the open nature of GNU / Linux has created a massive community that is actively involved in finding new ways to use it. Containers have evolved greatly through community participation. As the number of proficient network engineers in GNU / Linux grows, so will the use cases.