Staff Network Reliability Engineer (f/m/d)

At IONOS, the leading European provider of cloud infrastructure, cloud services and hosting services, you will work together with a wide range of teams. We are characterized by open structures, a friendly working culture and flat hierarchies with a strong team spirit. We firmly believe that work and fun are compatible, and offer you the right environment for this. Our constant growth means that we are always looking for new colleagues. Become part of IONOS and grow with us.

NRE Operations runs the data center networks for the entire IONOS group: the physical fabric and underlay, the SDN overlay, and the virtual network functions on top, across dozens of data centers. We are looking for a senior or staff-level engineer who operates large production networks with a reliability mindset. You define what "healthy" means, catch problems before customers do, lead the hardest incidents, and partner with NRE Automation to push routine operations toward zero manual steps. AI is central to how we work, both to make the network smarter and to make each engineer faster.

We expect every engineer here to be fluent with AI, and we mean it in two concrete ways. First, applying AI to the network itself: anomaly detection, automated diagnosis and root-cause analysis, config generation and validation, smarter alerting, and runbook or agent-driven automation. Second, using AI to raise your own output: coding assistants and LLM tooling for scripting, troubleshooting, research, and documentation. Reliability work punishes blind trust, so the skill that matters most is judgment. You need to know when an AI-generated config or diagnosis is trustworthy and when it is not.

Tasks

• Own reliability of the physical fabric, SDN overlay, and virtual network functions across all IONOS data centers. Set service level objectives and drive down unplanned downtime.

• Lead incident response on major network incidents and run postmortems that produce lasting fixes.

• Remove toil through automation, working with NRE Automation on pipelines and tooling for lifecycle, patching, and service configuration.

• Apply AI to operations: anomaly detection, automated diagnosis, config generation and validation, and automated remediation, with the judgment to know when AI output is trustworthy.

• Strengthen observability so problems surface before they reach customers, and shape lifecycle, upgrade, change-management, and capacity practices.

• Collaborate with NRE Provisioning on clean handovers.

• Share the on-call rotation covering the above.

Qualifications

• Extensive hands-on experience operating large-scale production data center networks (5+ years for Senior, longer for Staff).

• Deep Layer 2 and Layer 3 knowledge: routing (BGP, OSPF) and VXLAN with BGP/EVPN.

• Multi-vendor operations across Juniper and Cisco; SONiC and Netbox familiarity is a plus.

• Strong Linux fundamentals and the toolkit that goes with them (bash, tcpdump, iptables, git).

• Network automation you have built, using Python with Ansible and CI/CD on GitLab.

• A reliability-engineering mindset: SLOs, observability, incident command, postmortems, designing out toil.

• Fluent, critical use of AI in daily engineering, plus a track record or credible ideas for applying AI to network operations.

• Fluent English for international teams; German is a plus. Ownership and a calm approach when things break.

Benefits

• Hybrid working model.

• Flexible working hours through trust-based working hours.

• At some locations a subsidized canteen and various free drinks.

• Modern office space with very good transport connections.

• Various employee discounts for activities and products.

• Employee events such as summer and winter parties, as well as workshops.

• Numerous training and development opportunities.

• Various health offers, such as sports and health courses.

About IONOS

IONOS is the leading European digitalization partner for small and medium-sized businesses (SMB). The company serves around six million customers and operates across 18 markets in Europe and North America, with its services being accessible worldwide. With its Web Presence & Productivity portfolio, IONOS acts as a 'one-stop shop' for all digitalization needs: from domains and web hosting to classic website builders and do-it-yourself solutions, from e-commerce to online marketing tools. In addition, the company offers Cloud Solutions to enterprises who are looking to move to the cloud as their businesses evolve.

We value diversity and welcome all applications - regardless of, for example, gender, nationality, ethnic or social origin, religion, disability, age as well as sexual orientation and identity, physical characteristics, marital status or any other irrelevant factor subject to applicable law.