Systems Administrator, Senior
Confirmed on the employer's own hiring board on Nov 13, 2026. First seen by Alion on Nov 12, 2026.
Responsibilities
We are seeking a reliable and detail-oriented System Administrator to maintain, upgrade, and manage our software, hardware, and network infrastructure for our client. In this role, you will ensure high availability and security across all business systems while providing escalated technical support to end-users. The ideal candidate is a proactive problem-solver with strong organizational skills and a solid foundation in IT operations. This is a 3-5 month contract position reporting onsite at our client location in Green Bay, WI.
Qualifications
- Minimum of 7 years of experience in a network, systems administration, or infrastructure support role.
- Advanced experience designing, implementing, and troubleshooting Microsoft 365 environments.
- Strong expertise in Active Directory, Group Policy, Exchange, SharePoint, Hyper-V, and Microsoft Configuration Manager (SCCM/MECM).
- Hands-on experience with Windows Server administration, patch management, and system migrations.
- Experience with enterprise firewall administration, certificate management, and vulnerability remediation.
- Strong understanding of networking concepts, including routing, switching, TCP/IP, DNS, DHCP, and VPN technologies.
- Experience performing Cisco IOS XE upgrades and network device maintenance.
- Knowledge of cybersecurity best practices, security monitoring, and incident response procedures.
- Excellent troubleshooting, communication, and customer service skills.
- Legally authorized to work in the US without sponsorship
- Must demonstrate a “can-do” attitude
- We focus on candidates that display our “ACE” factor - Attitude, Compassion, and Enthusiasm to deliver quality solutions with exceptional customer service.
We focus on candidates that display our “ACE” factor - Attitude, Compassion, and Enthusiasm to deliver quality solutions with exceptional customer service.
What you get:
We offer weekly competitive pay, medical, dental, vision, 401K and more.
Overview
MOTIVATED…..make IT happen!
Sentinel Technologies, Inc. has been rated a top workplace every year since 2012!
About Us:
Sentinel delivers solutions that can efficiently address a range of IT needs - from security, to communications, to systems & networks, to software applications, to cloud and managed services; all of which include our staffing solutions for our clients. Since 1982, Sentinel has grown from providing technology maintenance services to our current standing as one of the leading IT services and solutions provider in the US. We have aligned with many of today’s global technology leaders including Cisco, Dell, VMware and Microsoft. Sentinel services customers both nationally and internationally with primary support operating centers in Downers Grove (HQ), Chicago, and Springfield, IL; Phoenix, AZ.; Lansing, and Grand Rapids, MI; Milwaukee, WI; and Denver, CO.
If you are MOTIVATED… you can make IT happen at Sentinel. Our commitment to our employees is to create a work environment that encourages creativity, an entrepreneurial spirit, fosters growth through certification and hands-on training, and values a team-oriented culture with rewards based on impact!
If you share our passion about what technology can do and want to be part of a top workplace environment - we’d like to have you join our team. Learn more at www.sentinel.com/careers.
As part of Sentinel's employment process, candidates will be required to complete a background check. Only those who meet the minimum requirements will be contacted. No phone calls please.
Sentinel is proud to be an equal opportunity employer including disability and veterans. In accordance with Title VII and state regulations, all qualified applicants will receive consideration for employment without regard to race, color, religion, age, sex, sexual orientation, gender identity, national origin, marital status, pregnancy, genetics, disability, military, veteran status or any other basis protected by law.
If you are an individual with a disability and need assistance in applying for a position, please contact [email protected].
The “Know Your Rights” Poster is available here
https://www.eeoc.gov/sites/default/files/2023-06/22-088_EEOC_KnowYourRights6.12ScreenRdr.pdf
Sentinel EEO Policy Statement is available here.
https://www.sentinel.com/about/diversity
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