System Administrator

About Cosigma.io

Cosigma is a French-Vietnamese engineering and IT consulting company operating between France and Vietnam. We support industrial and enterprise clients in digital transformation, custom software solutions, Product Lifecycle Management (PLM), and AI-driven platforms. We are currently expanding our footprint across Asia and developing new international partnerships and opportunities.

Role Overview

We are seeking a skilled and proactive System Administrator to manage, maintain, and optimize our Linux-based infrastructure and network environments. You will play a key role in ensuring system reliability, security, performance, and scalability while supporting virtualization, monitoring, automation, and containerized platforms

Your Responsibilities

Linux System Administration

• Manage, administer, and maintain Linux server environments.
• Ensure system availability, performance, security, and capacity planning.
• Perform system upgrades, patch management, and preventive maintenance.
• Analyze and resolve system performance issues and operational incidents.
• Implement and manage enterprise services including LDAP, Samba, and Traefik.

Virtualization & Infrastructure

• Deploy, maintain, and optimize virtualization platforms, primarily Proxmox.
• Manage virtual machines, storage resources, backup strategies, and disaster recovery processes.
• Ensure high availability and business continuity of critical infrastructure.
• Network Administration
• Configure and maintain network services including IP networking, routing, VLANs, DNS, and DHCP.
• Manage firewall and network security solutions such as IPTables and pfSense.
• Administer VPN solutions and secure remote-access infrastructures.
• Monitor, troubleshoot, and optimize network performance and connectivity.

Monitoring & Observability

• Deploy, maintain, and enhance monitoring and observability platforms including Zabbix, Centreon, Grafana, Telegraf, and InfluxDB.
• Develop dashboards, monitoring metrics, and alerting mechanisms.
• Proactively identify, investigate, and resolve infrastructure issues before they impact operations.

Containers & Automation

• Deploy and manage containerized workloads using Docker.
• Automate infrastructure provisioning, configuration, and operational tasks using Ansible.
• Continuously improve operational efficiency through scripting and automation.

Security & Compliance

• Implement security best practices across systems, networks, and services.
• Conduct vulnerability assessments, access control reviews, and security hardening activities.
• Maintain backup policies and disaster recovery procedures.

Required Skills & Qualifications

• Bachelor's degree in Computer Science, Information Technology, Network Engineering, or a related field.
• Minimum 1 year of experience in system administration or infrastructure operations, preferably in an international environment
• Strong expertise in Linux administration, system internals, troubleshooting, and shell scripting.
• Hands-on experience with Proxmox virtualization environments.
• Solid knowledge of networking fundamentals, routing, VLANs, DNS, DHCP, VPNs, and firewall management.
• Experience with monitoring and logging platforms such as Grafana, Zabbix, Centreon, Graylog, Elastic Stack, or similar tools.

Soft skills

• Strong analytical, debugging, and problem-solving skills.
• Strong ownership and accountability.
• Ability to work independently and manage multiple priorities.
• Effective communication and documentation skills.
• Collaborative mindset with a continuous improvement approach.

Languages

• Vietnamese: Full proficiency.
• English: good knowledge, both in writing and speaking

What We Offer

• Hybrid working arrangement: 50% in-office time
• 40 hours work week, from Monday to Friday
• Competitive compensation package, with bonus and year-end review
• 15 days of annual leaves
• Monthly team activities, team building
• Opportunity to grow and join our international team