Design, install and operate the internal network and server infrastructure of the L-mobile group, including continuous development
Plan and implement network segmentation and modern security measures (Firewall, WAF, IPS, MFA)
Operate and extend our hybrid and multi‑cloud and virtualization platforms (Microsoft Azure, Wortmann TerraCloud, VMware)
Take responsibility for the secure interconnection of our national and international sites, operate VPN solutions and comprehensively secure all endpoints
Maintain and monitor internal email systems including relevant security mechanisms (spam filters, SPF, DMARC, DKIM)
Work closely with management, the Head of Development, the CISO and external data protection officers to help shape the internal IT security strategy
Create and optimize concepts, policies and contingency plans for IT security and data protection
Plan budgets and act as the central interface between internal IT and software development
Document system configurations and support internal audits and security assessments

Completed IT training, a degree or an equivalent qualification (e.g., IT technician)
Initial relevant professional experience in network or server administration; practical experience is more important than the exact number of years
Solid knowledge of networking technologies such as VLAN, routing and VPN, and a basic understanding of IT security
Experience with virtualization, storage, backup and cloud infrastructures, preferably Azure, Veeam or VMware
Hands-on experience with firewalls, switches and security solutions, ideally Sophos and HP or Aruba systems
Strong knowledge of Windows Server administration and basic Linux skills
Very good English skills (C1 level) in speaking and writing and native-level German, as both languages are important for internal collaboration
High service orientation, strong analytical thinking and an independent, structured way of working
Strong communication skills and enjoyment of collaborating with internal business units

High flexibility: flexible working hours, mobile working, 30 days of vacation, working time account – overtime can be taken as time off
€50 tax-free monthly non-cash benefit in addition to salary via the Bonago card
Freshly prepared, tasty and subsidized daily lunch in our on-site canteen “Cooki Luki”
Freedom and dynamism: owner-managed company with no investor involvement
A great, diverse team that celebrates successes together and supports each other in challenging times
Grow beyond yourself: in-house Learning & Development and individual expert and leadership coaching
Additional perks such as ergonomic, modern workstations, JobRad (company bike leasing), company and sports events, beverages and fruit, company pension scheme, and more

Internal IT Infrastructure & Security Engineer

Key skills