Laurent Gehlen

Linux SME - UCB

Consultant NSI sa

08/2023 - 04/2024 (Current)

As Linux expert, I’m responsible for design and implementation of the Global Linux (RedHat) environment. I develop, automate and maintain configurations, deployment and maintenance utilities. I document procedures and practices.
I also manage the integrations of business applications and help the applications owners.
Furthermore, I had to lead the operational team in India.

Linux Specialist - IBA

Consultant Huxley IT

11/2018 - 06/2023

My first mission as consultant!

The goal was to automate the deployment of the IT rack which is shipped with the proton therapy solution. This deployment consist of hardware provisioning, building a virtualisation layer, installing the operating systems (Debian, OpenSUSE, SLES and Windows) with all the applications on top of it.

Automation and orchestration is done using Ansible. From the deployment of the bootstrap server (dhcp, PXE tftp boot, dns, mirror of distro repos), the switches' configuration (VLANs and IP helper), the generation on the fly of response files (kickstart/autoyast/preseed/unattend), the disks' encryption management, the ESXi nodes' provisioning followed by the complete VMware cluster build, the SAN's configuration and volumes presentations, the installation of prerequisite services for the business application (NFS, NTP, Samba,…).
All that automated deployment was also adapted to rebuild an entire IT infrastructure for treatment centre in a virtual environment (Proxmox). That allowed us to put in place a CI processes to test our changes, but also provide a cheapper environment for developers and QA testers that they are able to reprovision on demand.

DevOps - StepStone

Infrastructure Ops

09/2016 - 10/2018

As part of the Operations team, I participate into day to day tasks like systems upgrades (aptly, apt-dater). On the other hand, as DevOps I'm working in project mode to improve the infrastructure service.
By designing and deploying managed tools my goal is to provide automated and foundation services to my team but also to Devs and DevOps of other teams.

Freshly arrived at Stepstone, I directly took part in the main project: migration of the production platform from our regional data-center to AWS. I was in charge of the shared storage of the back-end servers (NFS + DRBD) and also of the DNS migration (Route53 + pdnsd).
Then, I proceed into the review of servers inventory tool (Django, Python, MySQL). Improvement of the content by data consolidation, extension of data model: ownership and patching groups definitions, API's extension: writing of Quality Check and input (apt-dater, ansible, ...) views.
I was also working on the implementation of Ansible for config management and the beginning of provisioning on AWS and Nutanix (KVM).

Unix Designer - GDF-Suez Electrabel

Expert System Designer

10/2007 - 08/2016

Within the IT department of GDF-Suez, I am the Linux expert, in charge of all technical Linux related matters/applications. In addition, I fulfil the role of security officer's relay for the Unix team. Below is a detailed, but not exhaustive list of tasks I carry out as part of my job:

Tech Watch: Testing new hardware and technologies, new OS versions, and new applications (System oriented).

3rd Line Support: Performing Root Cause Analysis of complex issues, providing solutions for challenging problems and following up cases with providers/suppliers.

Development / Scripting: Automizing tasks (KickStart files, installation scripts, ...), improving tools by writing plug-ins, and developping tools for internal usage (like management web interfaces or 'wrapper scripts').

Operational Tasks: Operating production for complex or undocumented tasks, implementing new tools and services for Operations (like Cobbler, MediaWiki, SVN Repo, or several web interfaces)

Technical Writing: Drafting official documentation (like Standards, conventions, and Production Hand Books) but also more personal documents (like HowTo, Cheat Sheet and Notes)

Project: Maintaining close contact with the customers and application owners, but also interacting with the other teams, and delivering documentation (See 'Tech Writing' > 'PHB') and implementations.