Senior System Administrator

This role is for one of Weekday’s clients

Min Experience: 5+ years Location: Bengaluru JobType: full-time

We are looking for an experienced Senior System Administrator to manage and maintain enterprise IT infrastructure, Microsoft 365 environments, endpoint security, cloud platforms, networking, storage, backup, and disaster recovery operations.

The ideal candidate will have strong expertise in Windows Server administration, Active Directory, and Microsoft 365, along with the ability to independently manage business-critical IT environments across on-premises, cloud, and hybrid infrastructures. The role requires a strong focus on infrastructure security, availability, scalability, redundancy, compliance, and operational excellence.

Key ResponsibilitiesEnterprise Infrastructure and Systems Administration• Manage enterprise IT infrastructure, including Windows Server 2012, 2016, 2019, and 2022 environments.

• Administer Active Directory, Forest and Domain Management, DNS, DHCP, DFS, Group Policy, WSUS, PKI, IAS/NPS, and File and Print Services.
• Perform server administration, operating system management, patching, migrations, cloning, capacity planning, health checks, and lifecycle management.
• Manage VMware vSphere and Microsoft Hyper-V environments, including VM provisioning, migration, cloning, snapshots, HA clusters, and resource optimisation.

Microsoft 365 and Identity Management• Administer Microsoft 365 services, including Exchange Online, Intune, Entra ID, Defender, Purview, Teams, SharePoint Online, OneDrive, and Windows Autopilot.

• Manage user administration, access controls, licensing, Role-Based Access Control (RBAC), Multi-Factor Authentication (MFA), Conditional Access, Single Sign-On (SSO), and identity governance.
• Manage Windows, macOS, Android, and iOS devices using Microsoft Intune, JAMF Pro, Apple Business Manager, and Mobile Device Management/Application Management (MDM/MAM).

Endpoint Security and Cybersecurity• Manage endpoint security, device compliance, device and application control, BitLocker encryption, EDR, XDR, antivirus, threat protection, and security baselines.

• Implement and maintain security solutions such as Microsoft Defender for Endpoint, Sophos Endpoint Security, McAfee ePO, email security gateways, and Data Loss Prevention (DLP).
• Perform vulnerability management, endpoint hardening, attack surface reduction, security assessments, and VAPT remediation.
• Manage Sophos firewalls, security policies, SSL VPN, IPSec VPN, Site-to-Site VPN, intrusion prevention and detection systems, NAT rules, application control, and web filtering.

Network Administration• Design, implement, and support enterprise LAN, WAN, WLAN, MPLS, and SD-WAN infrastructure.

• Manage routing, switching, TCP/IP, VLANs, NAT, wireless networks, and network segmentation.
• Configure and maintain Layer 2 and Layer 3 networking, including STP, RSTP, VTP, EtherChannel, Inter-VLAN Routing, and routing protocols.
• Manage routers, switches, access points, firewalls, and network security appliances.
• Ensure network availability, high availability, redundancy, and secure connectivity.

Cloud, Storage, Backup and Disaster Recovery• Manage Azure, AWS, and GCP environments, including compute, networking, storage, identity, governance, and cloud security.

• Administer NAS, SAN, RAID, storage replication, cloud storage, and capacity planning.
• Manage full, incremental, differential, image-level, VM-level, and cloud backups.
• Implement and maintain Disaster Recovery (DR) and Business Continuity Planning (BCP) processes.
• Ensure infrastructure redundancy, failover mechanisms, high availability, and operational resilience.

Monitoring, Maintenance and Compliance• Monitor infrastructure using PRTG, ManageEngine OpManager, Action1, Altris Patch Management, McAfee ePO, Azure Monitor, and security monitoring platforms.

• Perform preventive maintenance, root cause analysis, patch compliance checks, firmware upgrades, and security updates.
• Configure and support FTP, SFTP, FTPS, SSL certificates, SPF, DKIM, and DMARC.
• Support internal and external audits, security assessments, risk assessments, audit documentation, SOPs, and remediation plans.
• Manage vendors, OEMs, ISPs, software licensing, renewals, procurement coordination, budget planning, cost optimisation, and SLA governance.

Required Technical SkillsInfrastructure and Systems: Windows Server, Wintel, Active Directory, Forest and Domain Management, DNS, DHCP, DFS, WSUS, PKI, IAS/NPS, File and Print Services.

Microsoft Technologies: Microsoft 365, Exchange Online, Intune, Entra ID, Microsoft Defender Suite, Purview, SharePoint Online, Teams, OneDrive, Windows Autopilot, PowerShell.

Endpoint Security: Microsoft Defender for Endpoint, EDR, XDR, Endpoint Compliance, Device Control, ASR Rules, BitLocker, Endpoint Hardening, Application Control, Vulnerability Management, Sophos Endpoint Security, McAfee ePO.

Networking: TCP/IP, Routing and Switching, VLANs, VTP, STP, RSTP, EtherChannel, MPLS, SD-WAN, NAT, Wireless Networks, Routing Protocols.

Firewall and VPN: Sophos Firewall, SSL VPN, IPSec VPN, Site-to-Site VPN, IPS, IDS, Web Filtering, Application Control.

Cloud Platforms: Microsoft Azure, AWS, GCP.

Storage and Backup: NAS, SAN, RAID, Backup and Recovery, Disaster Recovery, Business Continuity Planning.

Virtualisation: VMware vSphere, Microsoft Hyper-V.

Monitoring and Patch Management: PRTG, ManageEngine OpManager, Action1, Altris, McAfee ePO, Azure Monitor.

Security and Compliance: DLP, Email Security Gateways, VAPT, Security Hardening, Vulnerability Assessment, Risk Management, Audit Support.

Must-Have Skills• Windows Server

• Active Directory
• Microsoft 365

Good-to-Have Skills• Cloud Platforms

• Apple Device Management
• Advanced Networking