The Linux Professional Institute (LPI) was born in October 1999, just five years after Torvalds' presentation. Over the past 20 years, LPI has earned a prominent place among the leading Linux certification providers.

The LPI program (referred to as the LPIC) is available in three distinct levels:

LPIC-1: Linux Administrator - A junior level Linux certification with no prerequisites, although having a Linux Essentials certification is recommended. Candidates must take two exams covering basic Linux skills, including working via the command line, performing basic maintenance tasks, installing and configuring a workstation (including X Windows), and making LAN or Internet connections. While it is possible to obtain the LPIC-1 credential directly from LPI, applicants should consider acquiring the CompTIA Linux + Powered LPI credential, which qualifies you for Linux + and LPIC-1 credentials.
LPIC-2: Linux Engineer - An advanced level Linux certification that requires the possession of an active LPIC-1 certification. Candidates must pass two exams covering significant Linux skills and topics. The first exam covers the kernel, system boot, filesystem and devices, advanced storage administration, network configuration, system maintenance, and capacity planning. The second exam covers web services, file sharing, network client management, e-mail services, system security and troubleshooting, and domain servers.
LPIC-3: Linux Enterprise Professional Certification - A Linux senior level certification that requires holding an LPIC-2 certification and passing a single 300 series exam. Currently valid exams include: 300: Mixed Environment, 303: Security and 304: Virtualization & High Availability. The Mixed Environment exam covers Samba (domain integration, user and group management, name services, configuration sharing, and so on), OpenLDAP, and collaboration with Linux and Windows clients. The Security exam covers network, operation and application security, as well as encryption and access controls. Finally, the Virtualization & High Availability exam covers the topics of storage, cluster management and virtualization.
In addition to the certifications listed above, the Linux Professional Institute also offers an entry-level certification, the Linux Essentials Professional Development Certificate (PDC) which focuses on the core skills: creating and executing simple scripts or restoring compressed backups and archives, working by line of command, the basics of the Linux operating system, FOSS, users and groups, file permissions for public and private directories. It is a great way to start acquiring the skills and knowledge necessary to face the most demanding certifications.

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