Senior System Administrator

About the role

We are seeking a Senior System Administrator to manage and scale multi‑cloud and on‑premise environments, including highly secure air‑gapped deployments for a banking client. The role combines infrastructure operations, security, and DevOps automation to ensure reliability, compliance, and performance.

Key responsibilities

• Administer Windows and Linux servers in cloud, on‑premise and isolated environments.
• Manage web servers (IIS, Apache, Nginx) and databases (MS SQL, PostgreSQL, MySQL).
• Maintain domain controllers, Active Directory, Azure AD (Entra ID) and group‑policy enforcement.
• Design and operate secure networks, VLANs, DNS/DHCP, load balancers and VPNs (IPSec, OpenVPN, WireGuard).
• Administer firewalls, WAF and Cloudflare services (DNS, CDN, Zero Trust).
• Implement CI/CD pipelines and Infrastructure as Code using Terraform and Ansible.
• Deploy and manage container platforms with Docker and Kubernetes.
• Set up observability stacks with Prometheus, Grafana and Wazuh SIEM.
• Ensure compliance with ISO 27001, PCI DSS and maintain audit‑ready documentation.
• Design high‑availability architectures and lead backup & disaster‑recovery planning, including immutable backups and DR drills.

Required profile

• 7‑10 years of experience in IT infrastructure, DevOps or related roles.
• Proven experience with Windows and Linux server administration.
• Hands‑on experience in air‑gapped, highly regulated environments.
• Strong knowledge of networking, VPNs, firewalls and Zero Trust security models.
• Demonstrated ability to build CI/CD pipelines and use IaC tools.
• Experience with container orchestration and monitoring solutions.

Required skills

• Windows Server, Linux (RHEL/CentOS/Ubuntu)
• IIS, Apache, Nginx
• MS SQL, PostgreSQL, MySQL
• Active Directory, Azure AD (Entra ID)
• VLAN, DNS, DHCP, load balancers
• IPSec, OpenVPN, WireGuard
• Firewalls, Cloudflare (DNS, CDN, Zero Trust, WAF)
• Terraform, Ansible
• Docker, Kubernetes
• Prometheus, Grafana, Wazuh
• ISO 27001, PCI DSS compliance
• Backup tools (Veeam, restic, Bacula)
• PowerShell, Bash, Python scripting