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Senior Systems & Network Administrator (Windows, Linux, Cisco & F5) Category: Infrastructure/Cloud
Main location: Canada, Ontario, Toronto
Position ID:J0926-2605
Employment Type: Full Time
Position Description: Position Summary
We are seeking a highly skilled Senior Systems & Network Administrator to join our Infrastructure & Operations team. This role is responsible for the administration, maintenance, monitoring, and support of enterprise Windows, Linux, virtualization, network, firewall, and load balancing environments.
The successful candidate will possess strong technical expertise in server administration, network infrastructure, virtualization technologies, and operational support processes. This individual will play a key role in ensuring the availability, reliability, security, and performance of critical business systems while supporting projects, incident management, change management, and continuous improvement initiatives.
This position requires a hands-on infrastructure professional capable of supporting server, network, and security technologies in a fast-paced enterprise environment.
Your future duties and responsibilities: Key Responsibilities
Systems Administration
• Administer, maintain, and support enterprise Windows and Linux server environments.
• Build, deploy, configure, patch, upgrade, and maintain physical and virtual servers.
• Manage Windows Server (2019, 2022 and newer) and Red Hat Enterprise Linux (RHEL 7, 8, and 9) environments.
• Perform system hardening, server lifecycle management, vulnerability remediation, and operating system upgrades.
• Manage backup, recovery, migration, and restoration activities.
• Review system, application, and infrastructure logs to proactively identify and resolve issues.
• Ensure server reliability, availability, and performance through ongoing monitoring and maintenance.
Virtualization & Infrastructure
• Administer and support enterprise virtualization platforms, including:
o VMware vSphere
o Microsoft Hyper-V
o KVM
• Provision and manage virtual infrastructure resources.
• Perform capacity planning and resource utilization analysis.
• Support infrastructure modernization, upgrades, and transformation initiatives.
Network, Firewall & Load Balancer Administration
• Administer and support enterprise network infrastructure and services.
• Manage and maintain Cisco Firewall environments, including:
o Firewall policy administration
o Access control management
o NAT configuration
o VPN administration
o Security rule reviews
o Troubleshooting connectivity and security issues
• Administer and support F5 BIG-IP Load Balancers, including:
o Virtual Servers
o Pools and Pool Members
o Health Monitors
o SSL Certificate Management
o Traffic Management Policies
o High Availability configurations
• Configure, manage, and troubleshoot:
o Site-to-Site VPNs
o Remote Access VPNs
• Assist with network design, implementation, and troubleshooting activities.
• Monitor network performance, traffic flows, and utilization trends.
• Support network security initiatives and infrastructure hardening activities.
• Analyze firewall logs, traffic reports, and packet captures to diagnose issues.
Core Infrastructure Services
• Administer and support:
o Active Directory
o DNS
o DHCP
o Group Policy
o NTP
o TCP/IP Networking
o Account Management
• Manage and troubleshoot file sharing technologies, including:
o NFS
o CIFS
o SMB
• Maintain permissions and access controls across server and storage environments.
Monitoring & Incident Management
• Review and verify:
o Infrastructure health reports
o Data integrity reports
o Resource utilization reports
o Monitoring alerts and notifications
• Intake, triage, investigate, and resolve incidents, service requests, and operational issues.
• Monitor system and network performance to minimize interruptions and maximize service availability.
• Participate in major incident response and restoration activities.
• Ensure incidents, requests, and tasks are updated and resolved within established service levels.
• Perform root cause analysis and contribute to problem management activities.
Change Management & Project Delivery
• Participate in change management and advisory processes.
• Create implementation, validation, and rollback plans.
• Maintain accurate records for infrastructure changes and operational activities.
• Provide infrastructure expertise and operational input during project planning and execution.
• Collaborate with architects, engineers, application teams, vendors, and business stakeholders.
Documentation & Continuous Improvement
• Create, maintain, and update:
o Technical documentation
o Standard operating procedures
o Knowledge base articles
o Infrastructure diagrams
o Configuration records
• Contribute to operational standards, automation initiatives, and continuous improvement efforts.
• Support knowledge transfer and mentoring activities within the team.
Required qualifications to be successful in this role: Required Qualifications
Education
• Degree or Diploma in Computer Science, Information Technology, or a related technical discipline.
• Relevant industry certifications are considered an asset.
Experience
• Minimum 5+ years of hands-on experience as a Systems Administrator supporting Windows and Linux environments.
• Experience supporting enterprise infrastructure in medium to large organizations.
• Experience working within a fast-paced operations environment.
• Experience supporting production-critical systems and business services.
• Demonstrated ability to manage multiple priorities and deliver results under pressure.
Technical Qualifications
Operating Systems
• Advanced administration experience with:
o Windows Server 2008, 2012, 2016 and newer
o Red Hat Enterprise Linux (RHEL 7, 8, and 9)
Virtualization
• Experience supporting:
o VMware vSphere
o Microsoft Hyper-V
o KVM
Windows Infrastructure
• Strong practical experience with:
o Active Directory
o DNS
o DHCP
o Group Policy
o Account Administration
o Windows Security
Network & Security
• Strong understanding of:
o TCP/IP
o Routing and Switching
o VLANs
o Network Segmentation
o VPN Technologies
o Network Security Principles
o SSL/TLS Certificates
o Load Balancing Concepts
• Hands-on administration experience with:
o Cisco Firewalls (ASA and/or Firepower)
o F5 BIG-IP Load Balancers
o Site-to-Site VPNs
o Remote Access VPNs
• Ability to troubleshoot issues across server, storage, network, firewall, and application layers.
Storage & File Services
• Experience with:
o NFS
o CIFS
o SMB
o Enterprise Storage Solutions
Enterprise Tools
• Experience using enterprise platforms for:
o Monitoring and Alerting
o Incident and Problem Management
o Change Management
o Ticketing Systems
o Knowledge Repositories
o SharePoint
Automation (Preferred)
• Experience with:
o PowerShell
o Bash
o Python
o Infrastructure automation tools
Desired Skills & Competencies
• Excellent analytical and troubleshooting skills.
• Strong understanding of system architecture, storage solutions, network topologies, and infrastructure security best practices.
• Ability to interpret system, application, firewall, and network logs.
• Strong customer service and service-delivery mindset.
• Excellent verbal and written communication skills.
• Strong organizational and time management abilities.
• Ability to work independently and collaboratively across technical teams.
• Strong attention to detail and commitment to operational excellence.
Preferred Certifications
• Microsoft Certified certifications
• Red Hat Certified System Administrator (RHCSA) or RHCE
• VMware VCP
• Cisco CCNA or CCNP
• F5 Certified Administrator (F5-CA)
• ITIL Foundation Certification
CGI is providing a reasonable estimate of the pay range for this role. The determination of this range includes factors such as skill set level, geographic market, experience and training, and licenses and certifications. Compensation decisions depend on the facts and circumstances of each case. A reasonable estimate of the current range is $85,000-$135,000. This role is an existing vacancy.
#LI-YK2
Skills: - English
- Linux
- VMware
- Windows Server
- F5
- Infrastructure
- Monitoring
