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 qualified 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

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.

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 multiple 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.

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.

Requirements

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.

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

Technical Skills Mandatory

Excellent working knowledge of firewall configuration and management for at least one of the following: Sophos XG, SonicWALL, Cisco Meraki or ASA

Technical proficiency with advanced networking skills such as: VLANs, Layer 3 switching, Mesh Wi‑Fi and IPsec VPN

Technical proficiency with server operating systems such as Microsoft Windows Server. Experienced configuring advanced features such as Azure AD, Azure AD Connect and Remote Desktop Services.

Technical proficiency with administration of Microsoft Office 365 / Exchange, and Google Workplace

Ability to install and support Microsoft desktop and server operating systems and related programs (including Active Directory management)

Ability to install and support Apple Mac OS/X desktop operating systems and related programs

Ability to design, install and support server and desktop virtualization environments built on VMware ESX/I and Microsoft Hyper‑V. Citrix Xen would be useful but not mandatory

Experience with remote access tools such as LogMeIn, TeamViewer, AnyDesk, etc.

Strong familiarity with Microsoft Office 365, Microsoft Exchange, SharePoint and SQL Server

Proficient with common peripherals: Printers, Routers, Wi‑Fi, UPS's, Firewalls, Switches

Proficient with basic hardware repairs, eg. replacing laptop hard drive, RAM upgrade, etc.

Experience supporting various disaster recovery solutions

Experience with cloud service platforms like Amazon AWS, Microsoft Azure, Google, and others

Proactive approach to support. Ability to identify problems in advance in order to continuously improve service delivery.

Proven problem solver

Self‑motivated and passionate about technology and IT support

Microsoft certifications (MCSA, MCSE)

Apple certifications

Cisco certification

Ability to perform simple cabling jobs (Cat 5e, Cat 6, patch panels, etc.)

Familiarity with Intuit QuickBooks

Familiarity with other key software applications, eg. Adobe Creative Cloud

Familiarity with Line‑of‑Business Software such as Sage One, Accpac, Spectra, Yardi, etc.

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.

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📌 Senior Technical Business Systems Analyst (Ontario)
🏢 AceStack
📍 Ontario