The people who teach
Teaches: Proxmox VE VMware Migration Proxmox Backup
Frank Bartkewitz
Training & Consulting Specialist
Frank started out with the German Armed Forces, where he earned a degree in geodesy and geoinformation before moving into IT. For the rest of his service he built and quality-assured the sysadmin training. He then spent over a decade at secunet Security Networks AG, from 2011, training more than 1,000 IT professionals in secure network and infrastructure administration. In 2020 he moved the lab infrastructure behind those trainings onto Proxmox VE and has been an enthusiast ever since. He joined croit in 2025 and certified as a Proxmox Trainer, and has since taught over 100 participants in certification courses plus another 80 in Proxmox VE and Backup Server workshops. He knows the territory around a topic as well as the topic itself, and gives all of it away in class.
Teaches: Ceph Proxmox VE Workshops
Alwin Antreich
Head of Training & Proxmox Services
Alwin has 20 years in IT behind him, several of them at Proxmox, writing code for the platform and moderating its community forum. He brought that ecosystem knowledge with him to croit, where he now represents the company at several conferences a year, often on the programme as a speaker. He heads training and Proxmox services, consults on projects built around Proxmox solutions, and is the colleague others turn to on Proxmox, and on Ceph, where he is equally at home. Ask him something narrow in a course and you get the full explanation, then the place in the documentation where it is written down, down to the individual option.
Teaches: Proxmox VE
Johnnie Kennedy-Foote
Training & Consulting Specialist
Johnnie learned virtualization by running it. At UKCEH he spent two years on a small team building an internal private cloud from nothing: a 10+ node Proxmox VE cluster that hundreds of colleagues depended on daily, with him responsible for clustering, high availability, networking, and live storage migrations on production workloads. He automated the VM deployments with Ansible. A year in IT consultancy after that taught him he liked the conversations as much as the configuration. At croit he teaches Proxmox VE and works with customers on their virtualization and storage. His interest runs to what happens underneath the hypervisor, and it doesn't switch off at the end of the day, there is a homelab, and it exists because he finds the subject interesting.
Teaches: Ceph
Gabriel Pérez Salgado
Consultant & Senior Support Engineer
Five years ago Gabriel was the one taking notes in croit's Ceph training. Since then he has spent his days on the cases that get escalated because the straightforward answers didn't work, and he now consults on Ceph and croit's products. That is an unusually good apprenticeship for a trainer: the material he teaches is the material he has watched break. He came to croit already knowing how to teach, from years as a Computer Networks instructor at Universidad Simón Bolívar in Venezuela. What he adds now is the examples, taken from real clusters and real failures, and a sense for which detail is about to trip up the person in front of him.
Our trainers cover for one another, so the trainer on a given date may differ from the one shown here.
Official Proxmox Training Partner and Gold Partner
