Senior Linux System Administrator Jobs in Ontario

Our client, a rapidly growing healthcare technology company supporting clinics across Canada and the U.S., is seeking a Linux Systems Administrator to help strengthen and scale their IT operations. 

In this role, you’ll take ownership of hybrid infrastructure spanning on-prem and cloud environments, ensuring performance, reliability, and automation at every level. From virtualization and networking to CI/CD and system monitoring, you’ll play a key role in maintaining a secure, high-availability environment that supports critical business systems. 

???? Who You Are 

You’re a versatile IT professional who thrives in complex environments and enjoys building resilient systems through automation. You bring a balance of hands-on technical skills, structured problem-solving, and a forward-thinking mindset. You’re comfortable managing both legacy and modernized platforms, ensuring infrastructure runs smoothly, efficiently, and securely. 

???? Work Type 

• Fully Onsite – 5 days a week in office 
• Location: Vaughan, ON 
• Vacancy Type: This is a newly created position 

Requirements

???? What You’ll Do (Your Superpowers) 

• Manage and maintain VMware, Proxmox, and Azure environments to ensure a stable, secure, and scalable infrastructure.
• Administer and optimize enterprise network infrastructure, including switches, routers, firewalls, VLANs, VPNs, and wireless connectivity to ensure reliable network performance.
• Configure and maintain pfSense, HAProxy, Cisco networking devices, and core network services (DNS, DHCP) to support high availability and secure connectivity.
• Implement and maintain network security best practices, including firewall policies, segmentation, access controls, and secure remote connectivity.
• Automate infrastructure provisioning, configuration, and deployments using Ansible and related automation tools.
• Oversee server hardware, NAS, and backup solutions, ensuring redundancy, disaster recovery, and data protection.
• Administer and optimize Linux and Windows servers, performing patching, performance tuning, and troubleshooting across both systems and network environments.
• Deploy and manage Docker and Kubernetes environments, improving application scalability and microservices performance.
• Monitor infrastructure and network health using Grafana, Prometheus, and Zabbix, implementing proactive alerting, logging, and performance monitoring.
• Manage and maintain MySQL, MongoDB, and SQLite databases with a focus on reliability, replication, backup, and performance optimization

⭐ What We’re Looking For (Our Wishlist) 

• 4+ years of hands-on experience in systems administration, network administration or infrastructure engineering 
• Strong understanding of Linux server administration (required), with experience managing Windows environments 
• Strong networking knowledge, including TCP/IP, routing, switching, VLANs, DNS, DHCP, VPNs, load balancers, and enterprise firewall administration
• Proven skills in virtualization platforms such as VMware and Proxmox 
• Hands-on experience configuring and troubleshooting network infrastructure, including Cisco networking equipment, pfSense firewalls, and high-availability networking solutions
• Experience implementing infrastructure and network security best practices, including segmentation, access controls, and secure remote connectivity
• Experience working in cloud environments (Azure preferred), including hybrid or multi-site architectures 
• Experience managing databases (MySQL, MongoDB, SQLite) for performance and reliability 
• Strong analytical and troubleshooting abilities with a focus on uptime, efficiency, and scalability 
• Excellent documentation, communication, and collaboration skills 
• A proactive mindset, always looking for opportunities to improve reliability and automate repetitive tasks 

???? What Makes This Role Exciting 

• Innovation & Impact – Work across cutting-edge cloud, virtualization, and infrastructure technologies to keep critical systems running efficiently 
• Autonomy & Ownership – Take the lead on infrastructure optimization, automation, and performance tuning projects 
• Continuous Learning – Expand your skills with modern tools and architectures across multiple environments 
• Collaborative Culture – Join a team that values curiosity, initiative, and innovation 

Benefits

• Base Salary: $90,000 – $110,000  
• Paid Time Off: Competitive vacation and personal days to maintain a healthy work-life balance 
• Health Spending Account & Dental Coverage: Flexible coverage to support your individual and family health needs  
• Culture & Team: Be a part of a supportive cross-functional team, that thrives on collaboration and innovation, where every member's ideas are valued and contribute to shared goals and success 

???? Ready to Elevate Your IT Career? Apply Now! 

At STACK IT Recruitment, we connect top technical talent with standout opportunities across Canada. If you meet at least 70% of the qualifications, we encourage you to apply — we’d love to chat! 

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✨ We’re proud to support diversity and inclusion. Need accommodation during the hiring process? Just let us know — we’re here to help. 

AI Use Disclosure:  
STACK IT uses AI-enhanced tools to support initial candidate screening and interview note analysis. All assessments and hiring decisions remain human-led.