Denis Hierholzer

Profile

Experience

1. Mar 2021 – Present5 yrs 9 mos

   IT Infrastructure Engineer

   Cilag AG – a Johnson & Johnson company · Schaffhausen, Switzerland

   Engineering and administration of the entire Schaffhausen OT infrastructure (LAN, firewalls, Linux and Windows servers, SAN).

   • Active Directory
   • Application streaming
   • Artificial Intelligence (AI)
   • Backup and archiving
   • Cisco ACI, classic routing and switching
   • Scripting (PowerShell and others)
   • Application development (Python)
   • Virtualization
   • OT cyber security (micro-segmentation, vulnerability management)

   • OT Security
   • Cisco ACI
   • AI
   • Python
   • PowerShell
   • Veritas NetBackup

   Projects & accomplishments (2)

   • Introduction of Cisco ACI. Replaced the Cisco SG500 core with an ACI spine/leaf fabric and introduced a new security zoning concept.
   • Introduction of Veritas NetBackup. NetBackup 9.1 on Red Hat 8.5 with a Dell ML3 tape library, iSCSI SAN, deduplication and tape encryption.
2. Jun 2020 – Feb 20219 mos

   IT Systems Engineer

   Syntegon Technology Services AG · Beringen, Switzerland

   Engineering and coordination of multiple infrastructure projects with a focus on networking (WAN, LAN, WLAN, DMZ, firewalls) and automation with PowerShell.

   • Networking
   • Firewalls
   • PowerShell
3. Jun 2014 – May 20206 yrs

   Lead Network and Security

   Schroder & Co Bank AG · Zurich, Switzerland

   Previously: Infrastructure Analyst / Systems Engineer (2014-06 – 2019-02)

   IT Operations department.

   • Administration and installation of Windows, Solaris, network and security systems
   • Operation of the T24 core banking application
   • VMware infrastructure including automated failover
   • System Center (SCCM, SCOM)
   • Security systems (DRM, DLP, Palo Alto and Check Point firewalls, privileged access management)
   • Process automation with PowerShell, e.g. a user account lifecycle tool

   • Palo Alto
   • Check Point
   • VMware
   • PowerShell
   • Security

   Projects & accomplishments (7)

   • Automated disaster recovery. Automatic failover of the virtual infrastructure to the DR site.
   • Firewall migration. Migrated proxy rules from Blue Coat ProxySG 600-20 to Palo Alto 5020 with Panorama and reduced the rule base by more than 50%.
   • User lifecycle automation. Modular PowerShell automation for user termination with HR/AD synchronisation and password-expiry notifications.
   • Data classification and encryption. AD RMS-based file classification and encryption (IQProtector) to meet FINMA requirements.
   • AppLocker rollout. AppLocker rollout with a self-developed GUI tool "AppLocker Mgmt Pro" that writes events to SQL Server.
   • PowerShell tooling. About ten tools, including a GUI for folder permissions, weekend wake/shutdown, RSA token provisioning, an Outlook button for SCSM tickets and the help desk tool "TSTool3".
   • Infrastructure modernisation. Migrated VBS logon scripts to group policies and DHCP to Windows Server 2012 R2.
4. Dec 2012 – Mar 20141 yr 4 mos

   Senior Systems Administrator / Systems Engineer

   Dentsu Holdings USA / 360i · New York City, USA

   Corporate IT managing about 10 branches and more than 300 servers worldwide in a mixed Windows/Linux environment.

   • Windows and Linux servers, VMware vSphere, Active Directory
   • SCCM, WSUS, McAfee ePO
   • Redmine, Atlassian Jira and Confluence
   • EMC NetWorker, Microsoft Exchange
   • Microsoft SQL Server including clustering, Apache Subversion including replication
   • Several PowerShell and VBS applications

   • VMware
   • SCCM
   • SQL Server
   • Linux
   • PowerShell

   Projects & accomplishments (4)

   • Active Directory maintenance framework. Modular framework with more than 1,500 lines of code.
   • Client management at scale. SCCM 2012 for 800+ workstations; WSUS for about 150 servers and 900+ workstations at 10 sites.
   • BitLocker. Disk encryption managed with SCCM, TPM and Active Directory.
   • More. Introduced Redmine, SQL Server failover cluster, McAfee anti-virus infrastructure, server inventory application, WordPress and SilverStripe site migration.
5. Jan 2011 – Oct 20121 yr 10 mos

   IT Officer

   Bomatec AG · Höri, Switzerland

   Responsible for all IT including project management.

   • Network services, help desk, newsletter operations
   • Windows 7 clients, Windows Server 2008 R2
   • Exchange 2010, Lync 2010, SQL Server
   • SAN, backup and ERP systems

   • Windows Server
   • Exchange
   • SCCM
   • Backup

   Projects & accomplishments (3)

   • Windows 7 migration. Migration to Windows 7 64-bit with SCCM.
   • Backup concept. Grandfather-father-son backup with Symantec Backup Exec 2012 and an HP tape autoloader.
   • More. Wi-Fi improvements and a new newsletter process.
6. Sep 2007 – Dec 20103 yrs 4 mos

   Systems Administrator / Systems Engineer

   Bucher Hydraulics · Klettgau, Germany

   Central IT managing 16 branches and about 100 servers worldwide.

   • Entire Lotus Notes / Domino infrastructure including the migration from version 7 to 8
   • Development and improvement of Notes applications

   • Lotus Domino
   • Windows Server
   • WSUS

   Projects & accomplishments (1)

   • Infrastructure projects. Corporate mobile device concept, P2V server migrations, video conferencing, Trend Micro anti-virus, WSUS patch management and an AD migration after a takeover.

Before graduation

1. Mar 2007 – Aug 20076 mos

   Web Developer (Diploma Thesis)

   eschbach IT GmbH · Bad Säckingen, Germany

   Diploma thesis "Conception and implementation of a Rich Internet Application based on an existing intranet application" (PHP, AJAX), the basis of today's Shiftconnector.

2. Mar 2006 – Aug 20066 mos

   Systems Administrator (Student Apprentice)

   Micronas GmbH · Freiburg, Germany

   Network administration, second-level support, server administration, scripting.

3. Sep 2004 – Feb 20056 mos

   Systems Administrator and First-Level Support (Student Apprentice)

   Harman/Becker Automotive Systems GmbH · Stuttgart area, Germany

   Network administration, first-level support, application development.

4. Aug 2002 – Sep 20022 mos

   Database Developer (Freelance)

   Textilbüro Weissenberger GmbH · Klettgau, Germany

   Microsoft Access database for order processing.

Volunteer work

1. Jan 2002 – Jul 202018 yrs 7 mos

   Volunteer Systems & Web Administrator

   Gemeindebücherei Klettgau (public library) · Klettgau, Germany

   User support, system administration (Windows Small Business Server 2003, Exchange, library software), and development of the public website. Officially honoured for volunteer work in January 2017.

Education

Certifications

• AINov 2026

  Claude Code Masterclass

  Verify

• SecurityNov 2025

  CISSP – Certified Information Systems Security Professional

  ISC2

  ID 3138351

  VerifyCertificate (PDF)

• OtherMay 2024

  Fitness Trainer B-License

  Certificate (PDF)

• NetworkJul 2019

  Cisco Certified Specialist – Enterprise Core

  Cisco · Passed CCNP SWITCH (300-115) and CCNP ROUTE (300-101)

  Certificate (PDF)

• SystemsNov 2018

  LPIC-1 Linux Administrator

  Linux Professional Institute

  VerifyCertificate (PDF)

• SecurityAug 2018

  Check Point Certified Security Administrator (CCSA) R80

  Check Point

  Certificate (PDF)

• SecurityFeb 2017

  Palo Alto Networks Accredited Configuration Engineer (ACE) PAN-OS 7.0

  Palo Alto Networks

  Certificate (PDF)

• SecurityNov 2016

  Cisco Certified Network Associate Security (CCNA Security)

  Cisco · Exam 210-260, NSA CNSS 4011 recognition

  Certificate (PDF)

• SecurityApr 2016

  Certified Ethical Hacker (CEH v9)

  EC-Council · Recertified, valid until April 2028

  VerifyCertificate (PDF)

• SystemsNov 2015

  Oracle Certified Associate, Oracle Solaris 11 System Administrator

  Oracle

  Certificate (PDF)

• OtherJan 2015

  Intensive Course Banking Fundamentals

  Fachschule für Bankwirtschaft

  Certificate (PDF)

• NetworkDec 2013

  Cisco Certified Network Associate Routing & Switching (CCNA R&S)

  Cisco

  Certificate (PDF)

• NetworkNov 2013

  Cisco Certified Entry Networking Technician (CCENT)

  Cisco

  Certificate (PDF)

• SystemsNov 2013

  VMware Certified Associate – Data Center Virtualization (VCA-DCV)

  VMware

  Certificate (PDF)

• SystemsMay 2012

  Microsoft Certified Solutions Associate – Windows Server 2008 (MCSA)

  Microsoft

  Certificate (PDF)

• SystemsMay 2012

  Microsoft Certified IT Professional – Server Administrator (MCITP:SA)

  Microsoft

  Certificate (PDF)

• SystemsAug 2010

  IBM Certified System Administrator – Lotus Notes and Domino 8.5

  IBM

  Certificate (PDF)

• OtherDec 2009

  Cambridge Certificate in Advanced English (C1)

  University of Cambridge

  Certificate (PDF)

• SystemsOct 2009

  IBM Certified System Administrator – Lotus Notes and Domino 8.0

  IBM

  Certificate (PDF)

• SecuritySep 2008

  Certified Data Protection Officer (IHK)

  IHK

  Certificate (PDF)

Independent coursework

• Oct 2024Proxmox VE Installation and Administration & Proxmox VE Advanced
• Nov 2021Red Hat Ansible for Network Automation (DO457)
• Nov 2021First Aid Training for Company First Responders
• Jan 2020Check Point Certified Security Expert R80.20 (CCSE)
• Jan 2020immocation Masterclass – Building Wealth with Real Estate
• Sep 2019Management Essentials Training (coaching, change and performance management)
• Jun 2019Cisco Implementing Cisco IP Routing (ROUTE 1.0)
• Mar 2019Cisco Implementing Cisco IP Switched Networks (SWITCH 2.0)
• May 2018Check Point Cyber Security Administrator R80.10
• Nov 2017Tanium 7 Foundation, Operations & IR Deep Dive
• Feb 2017Palo Alto Networks Firewall: Install, Configure, and Manage (EDU-201)
• Jan 2014PowerShell for the IT Administrator, Part 2 (Microsoft WorkshopPLUS)
• Jul 2013PowerShell for the IT Administrator, Part 1 (Microsoft WorkshopPLUS)
• Mar 2013Microsoft SQL Server 2008 Administration
• Jun 2011Planning, Deploying and Managing Microsoft SCCM 2007 (MOC 6451)
• May 2011OpaccOne for System Administrators (ERP)
• Apr 2011Microsoft Office 2010

Languages & commitment

Preferred work location

Within a radius of about 50 km around Klettgau, Germany, including Schaffhausen, Zurich and Winterthur.

Reference letters are available on request.