Network Administrator (m/f/d)

We are looking for a hands-on Senior Network Administrator to design, implement, and operate our enterprise network across multiple international sites. The ideal candidate brings deep expertise in next-gen firewalls (Fortinet & Cisco Firepower), enterprise switching (Cisco & Juniper), and network automation. You will define network architectures, harden security, streamline operations via scripting, and support site installations with regular travel within Germany.

Key Responsibilities

Architecture & Design

• Define scalable, secure LAN/WAN/SD-WAN architectures and standards for global sites
• Produce high-quality HLD/LLD documentation, network diagrams, IP schemas, and security policies
• Evaluate and select technologies aligned with performance, security, and cost goals.

Build & Implementation

• Install, configure, and optimize firewalls: Fortinet FortiGate and Cisco Firepower (including FMC, policy objects, IPS/IDS, SSL inspection, HA clustering, SD-WAN)
• Configure enterprise switches: Cisco Catalyst/Nexus and Juniper EX/QFX (VLANs, STP, LAG/MLAG, VRRP/HSRP, QoS, port-security, 802.1X)
• Implement site rollouts, migrations, and cutovers with minimal downtime
• Maintain and configure SASE platform

Operation & Security

• Own Level 3 incident/problem management; perform advanced troubleshooting (packet captures, flow analysis, logs)
• Maintain firewall and switch gold configs, rule hygiene, and change control (ITIL)
• Ensure compliance with security baselines, segmentation, and zero-trust principles
• Monitor capacity/performance and proactively remediate risks

Automation & Scripting

• Build and maintain automation for configuration, compliance checks, and deployments using Python and/or Ansible (e.g., templates, linting, CI/CD pipelines)
• Develop scripts for backup/restore, inventory, API-based object management (Fortinet/Cisco/Juniper)

Collaboration & Governance

• Work cross-functionally with Workplace, Cloud, Security, and Site Operations teams
• Support audits and contribute to policy development and continuous improvement
• Mentor junior engineers; act as technical escalation point

Travel

• Travel to German sites for installations, surveys, and hands-on support (approx. 10-25%, as needed)

Required Qualifications

• 5-8+ years in enterprise networking with multi-site/global exposure
• Proven expertise with Fortinet FortiGate and Cisco Firepower (FMC), including policy creation, NAT, VPN (IPsec/SSL), and HA
• Strong experience with Cisco and Juniper switching (Layer 2/3, routing protocols OSPF/BGP, EVPN/VXLAN nice to have)
• Solid understanding of network security (segmentation, NAC/802.1X, IDS/IPS, TLS inspection), DNS/DHCP/IPAM, and PKI fundamentals
• Automation: Proficiency in Python and/or Ansible for network tasks; experience with Git-based workflows
• Experience operating under ITIL (Change/Incident/Problem) and creating high-quality documentation
• Excellent communication skills; comfortable in an international environment.
• Language: Professional German and English are required
• Certifications (one or more of the following)

• Fortinet: NSE 4/5/6 (NSE 7 is a plus)

• Cisco: CCNP Enterprise or CCNP Security (CCIE a plus)

• Juniper: JNCIS-ENT / JNCIP-ENT (JNCIE a plus)

• Security: CompTIA Security+ or CISSP (plus)

Nice-to-Have

• Familiarity with cloud networking (Azure)
• Exposure to modern NAC (Cisco ISE, Aruba Clearpass), SASE/ZTNA, and wireless (Cisco Meraki, Juniper MistAI )
• Observability tools (e.g., SolarWinds, Zabbix, Grafana)