**ManTech** seeks a motivated, career and customer-oriented **Senior Principal Systems Engineer** to join our team in **Chantilly, VA** . The Senior Principal Systems Engineer is an instrumental part of a small, highly technical team providing WAN/LAN systems integration and support of a virtualized Windows client-server medium enterprise. The team consists of a technical Project Manager, four other Systems Engineers and a Help Desk supporting approximately 1,000 end users, three data centers, and 40 remote sites. **Responsibilities include but are not limited to** : + Develop recovery solutions to meet four-hour SLA + Make recommendations for technology and performance improvements based on system analysis + Work with the ISSO and take appropriate actions to maintain the system security posture IAW NIST 800-53 + Provide Tier3 support to the help desk staff as needed + Provide guidance and development recommendations to Systems Engineers + Assist the PM in system lifecycle planning **Minimum Qualifications** + Bachelor degree in Computer Science, Information Technology; an additional 4 years of Systems Engineering experience may be substituted in lieu of a degree + 10+ years of experience in the Information Technology field + 4 years in tandem of experience with user support and troubleshooting + 5 years in tandem of experience managing, troubleshooting, and operating various systems in small to medium Microsoft windows environments + 5 years in tandem of experience with Microsoft Windows Server and MS Office products + Proficiency with physical and virtual hardware/software (VMware), Active Directory, Exchange, SQL Server, Virtual Desktop Infrastructures (VDI), and Storage Area Networks (SAN). + DoD 8570 level II certifications: Security **Preferred Qualifications** + Experience working with Cyber Security engineer and ISSO to create/modify Group Policies, and balancing function and security when implementing STIG and NIST 800-53 controls. + Experience with networking to include VM Distributed Virtual Switches, Cisco switch port configurations, VLANs and VLAN trunks, OS firewall rules, and inline network encryptors + Experience installing and configuring Information Assurance tools, such as Trellix e-PO, endpoint security, centralized audit repositories, such as Splunk and/or InTrust + Experience installing and configuring VMware clusters, Horizon View VDI, and AppVolumes; VMware vSphere 7-8 certification training + Experience using PowerShell to automate tasks **Clearance Requirements:** + Must be a U.S. Citizen and have an active Top Secret security clearance **Physical Requirements:** + The person in this position must be able to remain in a stationary position 50% of the time. + Occasionally install rack-mounted equipment, connect wires under desks, and assist with equipment deliveries ManTech International Corporation, as well as its subsidiaries proactively fulfills its role as an equal opportunity employer. We do not discriminate against any employee or applicant for employment. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, or status as a protected veteran. If you are a qualified individual with a disability and require a reasonable accommodation to apply for a position with ManTech through its online applicant system, please email us at careers@mantech.com and provide your name and contact information.