Sr Systems Administrator

Experteer Overview Peraton seeks a Sr Systems Administrator to manage Windows/AD, on-prem Exchange, and VMware environments in Boston. You will oversee Exchange health, backups, retention policies, and email security via Proofpoint, while implementing DKIM/SPF/DMARC. You will monitor and optimize VMware and ESXi/vCenter, support AD, DHCP, DNS, GPOs, and perform upgrades. You’ll participate in after-hours rotation and help harden the virtualized infrastructure per CISA. This role supports critical national security IT operations with a hybrid onsite/remote schedule. Compensation / Benefits * Manage Windows/Active Directory environments (physical and virtual) * Maintain and monitor on-prem Microsoft Exchange environments, apply patches * Manage Proofpoint email security appliances and implement DKIM/SPF/DMARC * Coordinate backups with backup admins and participate in monthly restore tests * Manage email retention/archiving policies to meet legal requirements * Harden VMware environment and align with CISA recommendations * Configure and manage ESXi/vCenter, patching and performance tuning * Architect and implement virtualization standards; perform hardware refresh/build-outs * Implement and optimize AD core services (DHCP, DNS), group policy, OU replication * Provide after-hours support rotations * Develop and document virtualization procedures * Ensure protection against ransomware and modern threats to data * Collaborate with Cyber Security team on security hardening Tasks * Bachelor’s degree, 5 years of relevant experience OR Associate’s degree, 7 years OR High School diploma, 9 years * U.S. Citizen or Green Card holder, able to pass background check * Hands-on administration of MS Exchange, VMware infrastructure, and Windows AD * In-depth knowledge of Active Directory, DNS, and Windows core services * Experience managing private cloud and highly available virtual environments * Experience with HPE ProLiant servers * Proven experience designing and implementing ESXi/v8/v9 enterprise virtual infrastructure * Vendor and end-user troubleshooting experience * Ability to automate using scripts (PowerShell, Pearl, VBS) * Strong communication, analytical, and organizational skills * Ability to think strategically and prioritize multiple tasks Key requirements * overtime eligibility * shift differential * discretionary bonus * on-site parking * health benefits * retirement plan

_ and align with CISA recommendations * Configure and manage ESXi/vCenter, patching and performance tuning * Architect and implement virtualization standards; perform hardware refresh/build-outs * Implement and optimize AD core services (DHCP, DNS), group policy, OU replication * Provide after-hours support rotations * Develop and document virtualization procedures * Ensure protection against ransomware and modern threats to data * Collaborate with Cyber Security team on security hardening Tasks * Bachelor’s degree, 5 years of relevant experience OR Associate’s degree, 7 years OR High School diploma, 9 years * U.S. Citizen or Green Card holder, able to pass background check * Hands-on administration of MS Exchange, VMware infrastructure, and Windows AD * In-depth knowledge of Active Directory, DNS, and Windows core services * Experience managing private cloud and highly available virtual environments * Experience with HPE ProLiant servers * Proven experience designing and aaaaaaaaaa in ESXi/v8/v9 enterprise virtual infrastructure * Vendor and end-user troubleshooting experience * Ability to automate using scripts (PowerShell, Pearl, VBS) * Strong communication, analytical, and organizational skills * Ability to think strategically and prioritize multiple tasks Key requirements * overtime eligibility * shift differential * discretionary bonus * on-site parking * health benefits * retirement plan