Job Description
WE ARE HIRING!
Mainframe (Pvt) Limited is a fully owned subsidiary of Sumathi Holdings (Pvt) Limited, located in Colombo-03. We are hardware solution and service providers, renowned for our efficient work ethic and structured methodology. Our commitment lies in delivering top-notch technical solutions in the hardware domain.
We are looking for a Senior Systems & Infrastructure Administrator to join our infrastructure team, supporting IT operations across a diverse group of companies spanning multiple industries. This role will be responsible for day-to-day IT operations, including helpdesk support, endpoint and directory administration, infrastructure monitoring, troubleshooting, and vendor coordination.
JOB DESCRIPTIONS
- Helpdesk & Ticket Management
- Own and triage the day-to-day IT support ticket queue across departments and group companies.
- Resolve L1/L2 issues directly; escalate complex or architecture-level issues to the upper level.
- Track SLA adherence per the severity-based support framework and flag breaches early.
- Directory & Identity Administration
- Manage Active Directory and Microsoft 365/Entra ID: user/mailbox provisioning, deprovisioning, password resets, group and license management.
- Execute onboarding/offboarding checklists across the group companies.
- Maintain routine Exchange Online and Entra policy hygiene (retention, MFA enrollment, guest access reviews) as directed.
- Endpoint & Mobile Device Management
- Monitor CrowdStrike EDR alerts across 1,500+ endpoints; triage and action known/low-risk alerts, escalate suspicious activity immediately.
- Manage SOTI MobiControl enrollment, policy pushes, and routine troubleshooting devices.
- Coordinate endpoint patching and OS update rollouts.
- Network & Systems Monitoring
- Monitor the firewall, switch, and server health; log and respond to first-level alerts.
- Perform routine health checks on switches and firewalls (status, interface, PoE).
- Verify backup job completion and report failures.
- Vendor & Procurement Coordination
- Handle routine vendor calls, warranty/renewal tracking, and hardware/software procurement follow-ups.
- Coordinate with vendors (ISPs, security, hardware) on standard service requests.
- Documentation & Reporting
- Maintain up-to-date SOPs, asset records, and configuration documentation.
- Produce weekly status summaries for the manager covering tickets, monitoring, and outstanding items.
REQUIREMENTS
- Bachelor's degree/Diploma in IT, Computer Science, or a related field.
- 3+ years of hands-on experience in system/network administration.
- Working knowledge of Active Directory, Microsoft 365/Entra ID administration.
- Good understanding of firewalls, managed switches (Fortinet/Juniper/Cisco a plus), Windows, and Linux.
- Comfortable working with a ticketing system and following SLA-driven processes.
- Good written and verbal communication in English and Sinhala.
- Willingness to work in an ISO 27001-certified environment and follow documented procedures.