Mobileum · 6 hours ago
Senior System Administrator
United States
Full-time
Remote
Senior Level, Lead/Staff
12+ years expMobileum is seeking a highly experienced and self-motivated Senior System Administrator with a strong background in various technologies. This role involves managing enterprise-level systems, securing digital environments, and ensuring optimal IT performance across a hybrid IT landscape.
Telecommunications
Hiring Manager
Sridhar Rathod
Responsibilities
Manage, monitor, and maintain Windows Server infrastructure, including patching, performance tuning, and configuration
Provide expert-level support for Windows-based systems, ensuring high availability and security
Administer and support Microsoft 365 services including Exchange Online, SharePoint, Teams, OneDrive, and Security & Compliance Center
Manage hybrid identity using Azure AD, SSO, and directory synchronization
Implement and monitor policies using Microsoft Purview, DLP, and conditional access
Design, maintain, and secure on-premises Active Directory infrastructure
Perform regular audits, GPO configuration, OU structuring, and delegation of permissions
Deploy and manage email security solutions targeting phishing, spoofing, spam, and malware
Conduct phishing simulation campaigns and user awareness training programs
Evaluate and recommend security tools and protocols to protect organizational communication
Configure and maintain FortiGate Firewalls, including VPN, policies, routing, and IPS/IDS
Monitor and analyze network traffic to identify and respond to threats and performance issues
Provide support for Linux servers (Debian, RHEL, CentOS), focusing on scripting, updates, and integration with AD
Assist with cross-platform compatibility and troubleshooting
Implement and manage enterprise backup solutions such as Barracuda and Commvault
Define recovery point objectives (RPOs) and recovery time objectives (RTOs) for business continuity
Manage domain registrations, DNS configurations, SSL certificates, and hosting platforms
Liaise with hosting providers and ensure uptime and security of public-facing web services
End user computing and handle day to day operations related to Laptop, Desktop and Server Infra
Provide support to VIP users and Senior Executives independently
Manage Server, Laptop, Desktop Inventory
Qualification
Required
Bachelor's Degree in Computer Science, Information Technology, or a related field
Advanced knowledge on RHEL/Debian Operating System
12+ years of proven hands-on experience in system administration and infrastructure support
Advanced knowledge of Windows Server 2012–2022, Office 365, Azure AD, and email security tools
Hands on experience with FortiGate firewall and switches configuration and administration
Hands on experience on networking infra
Familiarity with industry best practices for cyber security and compliance
Knowledge of ITIL principles and implementation
Up to date with current technologies, trends, and security threats
Strong presentation skills and the ability to communicate complex technical concepts to non-technical stakeholders
Excellent reporting and documentation skills
Proactive, self-driven, and capable of identifying and closing operational gaps independently
Strong interpersonal and collaborative skills; able to work across teams and with vendors
Ability to manage time efficiently in a dynamic work environment
Preferred
Microsoft Certified: Azure Administrator Associate / Microsoft 365 Certified
ITIL Foundation Certification
RHEL Certification is preferred
Company
Mobileum
Mobileum is a leading provider of Telecom analytics solutions for roaming, core network, security, risk management, domestic and international connectivity testing, and customer intelligence.
1001-5000 employees
H1B Sponsorship
Mobileum has a track record of offering H1B sponsorships. Please note that this does not
guarantee sponsorship for this specific role. Below presents additional info for your
reference. (Data Powered by US Department of Labor)
Distribution of Different Job Fields Receiving Sponsorship
Represents job field similar to this job
Trends of Total Sponsorships
2025 (5)
2024 (10)
2023 (5)
2022 (4)
2021 (3)
2020 (5)
Funding
Current Stage
Late StageLeadership Team
Bobby Srinivasan
CEO
Avnish Chauhan
Co Founder, CTO, and EVP
Company data provided by crunchbase