Network Administrator

Sierra7, Inc. is seeking a Network Administrator to support the availability, security, and performance of a complex enterprise network serving a mission-focused federal organization. This role is responsible for maintaining network connectivity across office, data center, and cloud-connected environments; resolving advanced operational issues; improving monitoring and reliability; and supporting infrastructure modernization. The position works closely with other technology and security teams to reduce service interruptions, address vulnerabilities, and maintain consistent network standards. Work Schedule: Monday through Friday, 8:00 a.m. to 5:00 p.m. Eastern Time, excluding federal holidays and Government closures. Occasional evening or weekend work may be required for emergencies, maintenance, incidents, or other mission-critical needs. Position Responsibilities: Administer and support enterprise LAN, WAN, wireless, VPN, and cloud-connected network services.Configure, maintain, and troubleshoot routers, switches, firewalls, wireless access points, and related network appliances.Manage routing protocols, access controls, network segmentation, traffic prioritization, and secure remote connectivity.Monitor network health, capacity, availability, and security using enterprise monitoring and observability platforms.Investigate and resolve Tier II and Tier III network incidents, performance degradation, and service outages.Maintain network access control services, administrative authentication platforms, and endpoint posture controls.Support DNS, DHCP, IP address management, and certificate-related network activities.Apply firmware updates, security patches, configuration standards, and vulnerability-remediation actions to network devices.Create, test, maintain, and restore network-device configurations.Perform daily operational checks and identify potential issues before they affect users or critical services.Support planned maintenance, infrastructure upgrades, deployment activities, and network-improvement initiatives.Develop and maintain network diagrams, operating procedures, configuration records, troubleshooting guides, and other technical documentation.Participate in incident response, change control, problem management, and configuration-management processes.Work with systems, cloud, cybersecurity, service desk, and application teams to resolve cross-functional technical issues.Provide technical guidance to users, administrators, and other IT personnel.Support occasional evening or weekend maintenance, emergency response, or special operational activities when authorized.Perform work onsite at least three days per work week, with additional onsite attendance based on operational needs.