Install, configure, and maintain Linux/Windows servers (Ubuntu, RHEL, CentOS, Rocky,Windows 2022,2025 with AD,DNS,DHCP,GPO etc).Manage enterprise virtualization platforms - Proxmox VE and VMware (ESXi, vCenter).Support datacenter infrastructure operations across compute, storage, and network.Perform Linux OS hardening, patching, and security compliance.Tune and optimize OS and kernel performance (CPU, memory, disk, sysctl).Administer server networking: TCP/IP, VLANs, bonding, bridges, routing, and firewalls.