Full name

Dag Johan Maarten Wieërs


Ghent, Belgium


+32 478 436 299


Most recent résumé

Work experience

References available on request

Hewlett-Packard May 2010 → now (+4.9 years)

Linux System Developer/Engineer/Architect Troubleshoot Linux, SAN/multipathing problem. Best practices for Linux multipathing and SAN performance. Assessment and design of Linux reference architecture. Red Hat Satellite design. HP-UX ksh to Linux migration best practices. Incl. Belgian Federal Police, Dexia Technology Services, Atos Worldline, SWIFT, BNP Paribas Fortis, Belgacom / Proximus

Belgacom / Proximus Jan 2013 → now (+2.2 years)

Linux System Engineer Design and implement a monthly patching cycle for thousands of systems. Auto-process core-dumps and panics. Red Hat Satellite integration. Validating and improving security practices.

BNP Paribas Fortis May 2012 → Dec 2012 (7 months)

Linux System Architect Design, implement, automate and document a new Linux environment as part of a Solaris to Linux migration.

Belgian Federal Police May 2010 → Jun 2011 (1.6 years)

Linux System Developer Implement disaster recovery solution. Improvements to installation scripts, packaging and Webmin modules. Automation and integration. Design and implement a samba/anti-virus solution.

AXA Technology Services Nov 2007 → Mar 2010 (2.5 years)

Linux System Engineer Linux migration of Belgian data center to Germany. Design and implementation of modular framework and infrastructure for Linux and VMware ESX, used for deploying, retrofitting and validating Linux servers. 3rd level support, troubleshooting and design work.

EMC Jul 2007 → Dec 2007 (6 months)

Linux System Engineer (Short part-time assignment) Implementation of infrastructure for Novell SLES Linux deployment for technical development workstations. Integration with Active Directory, NIS, ClearCase and VMware.

Punch Telematix Jun 2007 → Sep 2007 (4 months)

Linux System Engineer (Short part-time assignment) Design and implementation of technical documentation system. Design and implementation of subversion. Packaging for Novell SLES Linux. Troubleshooting. Automation.

Euroclear Dec 2005 → May 2007 (1.5 years)

Unix System Engineer Deployment of Unix systems and services. Design and implementation of management infrastructure (configuration, documentation and change management). Packaging for Solaris, AIX, Linux and VMware. Custom software development. Troubleshooting. Automation.

IBM internship 1999; Sep 1999 → Dec 2005 (5.5 years)

Unix System Engineer On Unix and Linux systems. (e.g. packaging on Linux/AIX, implementing various system and network services, general troubleshooting), implementing hosting infrastructure on Linux. (e.g. resource and availability monitoring, capacity planning, firewall framework)

Consultant Designing and implementing solutions for automatic deployment of Linux clients, Point-Of-Sale systems, network services, clusters and big parallel storage systems for digital media projects, incl. Real Software, VRT, EVS, RVA, Callataÿ & Wouters, KBC

Mind Linux Solutions Oct 1999 → Apr 2001 (1.6 years)

Founder / Business Unit Manager Taking care of various parts of the organization, including sales and marketing. Experience with project-management and pre-sales for a small (15 headcount) consultancy company.

Consultant Linux and Open Source consulting and training for several customers in on-site projects varying between 1 and 3 weeks.

Provinciale Bibliotheek Limburg voluntary 1996-1997

System/Network Administrator Maintenance of 12 public Internet terminals (based on Windows 95) and an ISDN Internet connection.

Internet Trainer Individual training and training in group regarding computer use, the Internet, search-engines and popular websites.

SISA Software / Winsome summer job 1996-1997

Consultant Analysis and design of an off-line website generation program (further developed as WebEngine) and web-scripting. Implementation of business projects.

System Administrator Installation and operational management of Linux infrastructure and routers.



  • Analytical - ability to quickly learn and understand from self-study or analysis.

  • Structured - good understanding of project management and change management.

  • Thorough experience in Unix system administration, advanced automation and orchestration.

  • Thorough experience in configuring and deploying systems in a scalable and coherent manner.

  • Owner of various best practices regarding Linux system and application deployments, system maintenance and documentation, system security and Enterprise Linux in general.

  • Experience in developing and marketing products using the Internet and Internet communities.

  • Experience in project management and leading technical teams.


  • Direct communication skills - does not overpromise or underdeliver.

  • Team player - listen, share, cooperate and learn together as a team.

  • Presentation skills - experience with presenting for large groups in international settings.

Systems architecture

  • Experience with designing Standard Operating Environments (SOE) and automating Unix-to-Linux projects.

  • Experience with designing Linux security standards and processes to harden existing environments.

  • Experience with designing Linux life cycle management and security patch management processes.

  • Experience with designing infrastructure for systems management, troubleshooting, monitoring and automating environments.

Systems engineering

  • Excellent knowledge of Red Hat Enterprise Linux internals, security best-practices, performance tuning and troubleshooting.

  • Thorough experience with enterprise automation and orchestration using Ansible and Red Hat Network Satellite and integrating with enterprise CMDB solutions.

  • Thorough experience with Red Hat kickstart and post-installation mechanisms for rapid mass deployment.

  • Thorough experience with building packages and automating enterprise software deployment.

  • Thorough experience in designing and implementing a multi-customer monitoring and reporting infrastructure.

  • Yearly attendance of various specialty conferences on Systems Architecture and Systems Engineering to discuss designs, implementations and tools in detail.

  • Years of operational experience in Unix environments.

Operating systems / Software

  • Excellent knowledge of Linux (since 1994) including Red Hat Enterprise Linux, Scientific Linux, CentOS, Fedora (but also SLES, Ubuntu, Debian, …).

  • Experience with various Unix systems including AIX, HP/UX and Solaris, mostly related to packaging, automation and troubleshooting. Limited hardware knowledge.

  • Thorough experience with configuration management tools (Ansible and Puppet) and inventory management.

  • Experience with managing and integrating with virtualization solutions, including OpenVZ, RHEV/KVM and VMware vSphere.

  • Experience with clustering, load-balancing, fail-over and disaster recovery techniques.

  • Experience with firewalling, virtual private networking and network intrusion detection (NIDS).

  • Thorough experience in compiling, installing, and configuring of Unix system software, e.g. NFS, Samba, lpd and cups, Postfix, Amavisd, Bind, DHCP, XFree86, Apache, ssh, ntpd, Snort, Dante, RRDtool, Nagios, Webmin, Relax-and-Recover, KVM, …

  • Experience with GPFS clustering and SAN environments (eg. for large digital media environments).

  • Experience with various markup languages (HTML, SGML, DocBook, XML, CSS, AsciiDoc, Markdown).

  • Experience with filtering, troubleshooting and programming TCP/IP network protocols.

  • Experience with managing and troubleshooting SQL servers (MySQL, PostgreSQL, DB2 and some Oracle) and applications using SQL.

Programming languages


Lua since 2006, Python since 2002, SQL since 1997, PHP since 1996, JavaScript since 1995, Bash and Unix shells since 1994, C since 1994, Perl since 1994


C# and Mono 2003 - 2005, RPG on AS/400 1997 - 1998, Visual Basic 1997, Java 1996 - 1999, x86 Assembler 1992 - 1996, Pascal 1991 - 1999, Basic 1988 - 1990


  • Dutch: native

  • English: fluently spoken and written

  • French: basic spoken and limited written

  • German: notions


International conferences

Since 1997 I frequently attend international conferences related to Linux, Open Source, System and network security, Systems architecture, Automation, Programming, Configuration management, Monitoring, Devops, etc.

Public speaking

On various occasions I have presented about different Linux and Open Source topics, including at the following conferences:

  • Ansible Meetup, Utrecht, NL 2015

  • NLUUG, Utrecht, NL 2014

  • LinuxTag, Berlin, DE 2008, 2012, 2014

  • FlossUK, UK 2012 - 2014

  • CfgMgmtCamp, Ghent, BE 2014

  • LOADays, Antwerp, BE 2012, 2013

  • T-DOSE, Eindhoven, NL 2007 - 2012

  • ODF Plugfest, Brussels, BE 2012

  • LinuxCon Europe, Prague, CZ 2011

  • LibreOffice Conference, Paris, FR 2011

  • Linux Symposium, Tokyo, JP 2009

  • FrOSCon, Bonn, DE 2007 - 2009

  • FOSDEM, Brussels, BE 2007 - 2009

  • JRSL, Buenos Aires, AR 2008

  • NLLGG, Utrecht, BE 2008

  • LinuxWorld Expo, Brussels, BE 2008

  • LinuxWorld Expo, Utrecht, NL 2007

  •, Cambridge, UK 2007


Red Hat certification verify

  • Red Hat Certificate of Expertise in Performance Tuning (RH442)

  • Red Hat Certified Engineer (RHCE) - Score: 100%

  • Red Hat Certified System Administrator (RHCSA) - Score: 100%

Linux Professional Institute certification verify

  • LPI Certification Level 3 (LPIC-3) - Senior level

  • LPI Certification Level 2 (LPIC-2) - Advanced level

  • LPI Certification Level 1 (LPIC-1) - Junior level

Brainbench certification verify

  • Linux Administration (General) - Score: 94%

Technical writing

IBM Redbook Residency, Poughkeepsie, NY May 2005

Co-written an IBM Redbook about the design and implementation of GPFS (General Parallel File System) in a digital media (broadcasting) environment. [SG246700]

IBM Redbook Residency, Austin, TX Nov 2002

Co-written an IBM Redbook about the design and implementation of a Linux-based deployment in a branch banking environment. [SG246813]

Formal education

XIOS Hogeschool Limburg, Diepenbeek 1996 → 1999

Applied Computer Science (~ Bachelor degree)

Universiteit Hasselt, Diepenbeek 1994 → 1996

Computer Science, 1st year

Heilig Hartcollege, Heusden-Zolder 1988 → 1994

Latin-Greek, Latin-Mathematics and Science-Mathematics

Additional activities

  • Maintainer of RPMforge RPM repository with more than 5000 Open Source software RPM packages for RHEL, Scientific Linux and CentOS used by many international companies and organizations.

  • Member of the ELRepo project providing kernel module packages (hardware drivers) used by many international companies and organizations using RHEL, Scientific Linux or CentOS.

  • Author of various Open Source software projects including:

    • ansible-provisioning: set of modules and methodology to do provisioning using Ansible

    • dstat: flexible real-time system resource monitoring tool

    • vmguestlib: python library to access performance counters from within VMware guests

    • asciidoc-odf: convert AsciiDoc markup directly into formatted ODF documents (used for this CV)

    • mrepo: manage repositories and synchronize from various sources

    • dconf: make hardware and software configuration snapshots for troubleshooting and comparison

    • unoconv: convert office documents from one format to another using OpenOffice/LibreOffice filters

    • wiipresent: using Wii remotes as a remote control device

  • Contributor to various Open Source projects including:

    • Ansible, Relax-and-Recover, OpenELEC, XBMC, AsciiDoc, docbook2odf, Proxytunnel, scannedonly, …

  • Ex-member of the CentOS core team

  • CoderDojo mentor fostering children’s enthusiasm for Scratch programming and Arduino engineering

  • Author of the FrOSCon LiveUSB used for informational displays and conference room computers