24x7 Senior System Engineer – Windows, VMware & Security

Sciente International Pte Ltd; Singapore; On-site; SGD 90,000 - 120,000; Full time

Job summary

Sciente International Pte Ltd in Singapore seeks a hands-on Senior System Engineer to lead and support 24x7 mission-critical systems in secure on-prem environments. The role requires strong technical expertise, operational leadership, with hands-on involvement in deployments, critical incidents, and emergency recovery activities.

The ideal candidate has 5+ years of experience in systems administration or infrastructure support, with hands-on proficiency in Windows Server, AD, GPO, SQL Server,

Qualifications

• Minimum 5 years in Systems Administration, Infrastructure Support, or Mission-Critical environments.
• Hands-on with Windows Server, Active Directory, GPO, and Microsoft SQL Server.
• Experience with VMware, Layer 2/3 networking, and Splunk monitoring.
• Knowledge of backup/recovery, disaster recovery, patching, and cybersecurity solutions.
• Experience supporting 24x7 on-premises systems.
• Strong troubleshooting, problem-solving, and analytical skills.
• Willing to provide on-site support for critical incidents and emergency recovery, including after-hours, weekends, and public holidays.

Responsibilities

• Administer and maintain Windows servers, workstations, and Active Directory environments.
• Manage antivirus definitions, security patches, OS, software, and firmware upgrades.
• Perform SSL certificate renewal and management across all system components.
• Maintain and manage VMware virtualization infrastructure including ESXi, vCenter, vSAN, and NSX.
• Monitor and manage system logs using Splunk and Syslog tools.
• Troubleshoot system issues and coordinate with OEM vendors for root cause analysis and resolution.
• Perform monthly preventive maintenance, system health checks, and reporting.
• Support system deployment and change activities during off-peak hours.
• Manage L1-L3 incident tickets and service requests.
• Provide 24/7 Level 2 operational support based on a scheduled rotation.

Skills

Mission-critical experience

Windows Server

Active Directory

GPO management

Microsoft SQL Server

VMware virtualization

Layer 2/3 networking

Splunk monitoring

Backup and disaster recovery

On-site incident response

Troubleshooting and analytical skills

Tools

ESXi / vCenter / NSX

Splunk

Windows Server administration

Active Directory management

Job description

Sciente International Pte Ltd in Singapore seeks a hands-on Senior System Engineer to lead and support 24x7 mission-critical systems in secure on-prem environments. The role requires strong technical expertise, operational leadership, with hands-on involvement in deployments, critical incidents, and emergency recovery activities.

The ideal candidate has 5+ years of experience in systems administration or infrastructure support, with hands-on proficiency in Windows Server, AD, GPO, SQL Server,