Senior Systems Administrator - Level 2/3 Managed Services

Senior Systems Administrator – Level 2/3 Managed Services
Location: Midtown Toronto, ON
Work Arrangement: Primarily office-based with flexibility for remote work and scheduled client/site visits
Job Type: Full-Time, Permanent
Salary: $85,000 – $110,000 per year, based on experience and qualifications
Bonus: Up to 10% annual performance-based bonus
About the Role

Our client is a growing managed IT and security services organization supporting professional services, legal, and commercial real estate clients across North America. They are seeking a Senior Systems Administrator to take ownership of complex client environments from day-to-day operations through project delivery.

This is a senior, client-facing technical role that combines systems and network administration, Microsoft 365, cybersecurity, managed services, and building technology environments. The successful candidate will serve as a senior escalation point for Level 1/2 technical issues while also providing day-to-day technical direction and mentorship to junior technicians.

The role offers broad exposure across multiple client environments rather than being dedicated to a single account, making it an excellent opportunity for an experienced MSP professional who enjoys variety, problem-solving, client interaction, and technical ownership.

Key Responsibilities
Systems, Network & Client Environment Management

• Manage day-to-day network and systems operations across multiple client environments, including servers, firewalls, switches, Wi-Fi, and endpoints.
  
• Serve as a senior escalation point for Level 1/2 technical issues and drive incidents through to resolution.
  
• Lead patch management, firmware updates, maintenance windows, and infrastructure upgrades while minimizing business disruption.
  
• Maintain accurate technical documentation, including network diagrams, credentials, run-books, and client environment information.
  
• Support legal and professional services applications, including document and practice management platforms.
  
• Provide hands-on technical support across diverse client environments.
  

Microsoft 365 Administration

• Administer Microsoft 365 environments end-to-end, including Exchange Online, SharePoint, Teams, OneDrive, licensing, and user provisioning.
  
• Configure and maintain Microsoft 365 security controls, including Conditional Access, MFA, Intune, Defender for Office 365, and Data Loss Prevention.
  
• Manage Microsoft Entra ID/Azure AD, including hybrid Active Directory synchronization, user and group management, and single sign-on.
  
• Lead and support migrations from on-premises infrastructure to Microsoft 365.
  
• Monitor tenant health, licensing, security, and compliance across multiple client environments.
  
• Maintain accurate documentation of Microsoft 365 configurations, licensing, and security settings.
  

Cybersecurity & Security Operations

• Administer and maintain endpoint detection and response (EDR) solutions across client environments.
  
• Monitor and respond to security alerts, investigate detection, and coordinate remediation activities.
  
• Work with external managed detection and response/SOC providers on security investigations and escalations.
  
• Ensure appropriate endpoint and network coverage across managed environments.
  
• Support SIEM log source onboarding and monitoring.
  
• Participate in vulnerability remediation, security posture reviews, and cybersecurity maturity initiatives.
  
• Document security incidents, remediation activities, and lessons learned.
  

Managed Building Technology & OT

• Support network and infrastructure operations across multi-building commercial property environments.
  
• Manage servers, domain controllers, endpoints, networks, and operational technology (OT) systems.
  
• Administer Nutanix hyper-converged infrastructure, including cluster health, virtual machines, and routine maintenance.
  
• Support network segmentation and firewall management to isolate OT environments.
  
• Assist with EDR/MDR monitoring and firewall log reviews.
  
• Manage vendor remote access, including VPN provisioning, credential audits, and access registers.
  
• Participate in vulnerability scanning, remediation tracking, and cybersecurity initiatives across building networks.
  

Team Leadership & Mentorship

• Provide day-to-day technical direction to Level 1 technicians and help prioritize incoming work.
  
• Review Level 1 ticket resolutions for quality, completeness, and adherence to documentation standards.
  
• Act as the first escalation point for junior technicians.
  
• Mentor and coach technicians on troubleshooting methodology and best practices.
  
• Assist with onboarding and training new technical team members.
  
• Identify recurring issues and drive root-cause solutions and process improvements.
  

Projects & Client Relationships

• Lead or support infrastructure projects, including server migrations, Microsoft 365 projects, and building technology initiatives.
  
• Develop strong relationships with client stakeholders and act as a trusted technical advisor.
  
• Communicate technical information effectively to both technical and non-technical stakeholders.
  
• Deliver a high level of customer service within professional, confidentiality-sensitive client environments.
  
• Participate in strategic service delivery initiatives as the organization continues to grow.
  

RequirementsRequirements

• 5+ years of experience in systems/network administration within an MSP or similar multi-client environment.
  
• Hands-on experience with an RMM and PSA platform used for ticketing, SLA management, monitoring, and reporting.
  
• Experience with platforms such as HaloPSA, NinjaOne, ConnectWise, AutoTask, or similar.
  
• Experience administering Nutanix HCI, including cluster management and AHV/VM administration.
  
• Strong experience with Microsoft 365 administration, including Exchange Online, SharePoint, Teams, and OneDrive.
  
• Hands-on experience with Microsoft 365 security features, including Conditional Access, MFA, Intune, Defender for Office 365, and DLP.
  
• Practical knowledge of on-premises Active Directory, Microsoft Entra ID/Azure AD, and hybrid environments.
  
• Experience supporting or leading migrations from on-premises infrastructure to Microsoft 365.
  
• Solid understanding of networking concepts, including LAN/WAN, VLANs, and firewalls. FortiGate experience is an asset.
  
• Familiarity with EDR/MDR platforms and fundamental security operations concepts.
  
• Experience mentoring, coaching, directing, or reviewing the work of junior technicians.
  
• Strong client-facing communication skills with the ability to work comfortably with non-technical stakeholders.
  
• ITIL Foundation certification or working knowledge of ITIL incident, change, and problem management is an asset.
  
• Experience supporting law firms, professional services organizations, or commercial property environments is an asset.
  
• Experience with operational technology (OT), building automation systems, or multi-site commercial environments is an asset.
  
• Valid Ontario driver's license and reliable vehicle preferred.
  
• Must be able to complete a criminal background check before employment successfully.
  

BenefitsCompensation & Benefits

• $85,000 – $110,000 base salary
  
• Annual performance bonus of up to 10%
  
• Comprehensive health, vision, and dental benefits, including family coverage
  
• Three weeks of paid vacation to start
  
• Additional vacation entitlement based on tenure
  
• Professional development, training, certifications, conferences, and professional memberships
  
• Ongoing coaching and career development opportunities
  
• Flexible remote work options alongside scheduled office and client/site visits
  
• Free nearby parking
  
• Company-provided laptop and required business tools
  
• Mileage reimbursement for approved business travel
  
• Collaborative, team-oriented work environment with direct access to leadership
  

Why Join?

This is an opportunity to join a growing managed services organization in a senior technical capacity with broad exposure to legal, professional services, and commercial real estate environments.

The successful candidate will have the opportunity to work across a diverse client portfolio, influence service delivery processes, mentor junior technicians, contribute to infrastructure and cybersecurity projects, and play an important role in the organization's continued growth.

Schedule: Monday to Friday, 7.5-hour shifts, with a scheduled after-hours on-call rotation.