Senior Linux Administrator

Summary:

The Associate Principal, Linux Administrator is responsible for managing and maintaining enterprise Linux server environments through hands-on daily operational activities. This role ensures the stability, performance, security, and availability of Linux infrastructure across on-premises and cloud environments. The position requires strong operational expertise, a proactive approach to system health, and the ability to work across US Day and night shifts to provide continuous 24/7 coverage for critical infrastructure.

Primary Duties and Responsibilities:

To perform this job successfully, an individual must be able to perform each primary duty satisfactorily.

• Monitor, manage, and maintain enterprise Linux server environments (RHEL, CentOS, Ubuntu, Amazon Linux) on a day-to-day basis across on-premises and cloud infrastructure
• Perform routine system health checks including CPU, memory, disk utilization, and process monitoring across all Linux servers
• Respond to system alerts, service failures, and performance degradation in a timely manner; triage and resolve incidents within defined SLA windows
• Manage user accounts, groups, permissions, and SSH key administration across Linux systems
• Administer cron jobs, scheduled tasks, and system services (systemd, init) to ensure uninterrupted operations
• Perform log analysis and monitoring using tools such as journald, rsyslog, ELK Stack, Splunk, or CloudWatch to identify anomalies and recurring issues
• Execute day-to-day storage operations including LVM management, filesystem extension, NFS mount management, and disk space remediation
• Troubleshoot OS-level issues including boot failures, kernel panics, network connectivity problems, and service disruptions
• Coordinate and execute scheduled maintenance activities including reboots, service restarts, and configuration updates during approved change windows
• Apply security patches, kernel updates, and bug fixes to Linux servers in alignment with the enterprise patching schedule using Red Hat Satellite and Ansible Automation Platform (AAP)
• Validate patch deployments in non-production environments prior to production rollouts and perform post-patch validation checks to confirm system stability and service availability
• Support emergency and zero-day vulnerability patching as directed by the security team
• Enforce CIS benchmark standards and security baselines on Linux systems; remediate non-compliant configurations
• Perform periodic security scans using OpenSCAP, Lynis, or Nessus and document findings for remediation tracking
• Actively manage incidents, service requests, and change records using ServiceNow, ensuring timely updates, proper categorization, and SLA compliance
• Serve as an escalation point for Tier 1/Tier 2 Linux issues during assigned shift
• Participate in root cause analysis (RCA) and post-incident reviews for major Linux-related outages
• Execute approved change requests during maintenance windows including patching, configuration changes, and server builds
• Maintain clear and accurate shift handover notes to ensure operational continuity across US day and night shifts
• Provision new Linux servers (physical, virtual, and cloud) following approved build standards and golden image baselines
• Configure servers post-build including network settings, storage mounts, security hardening, and application-level prerequisites
• Support AMI (Amazon Machine Image) updates and golden image refreshes for AWS EC2 instances
• Execute Ansible playbooks for configuration management, compliance enforcement, and routine operational tasks
• Proactively monitor infrastructure dashboards (Nagios, Prometheus, Grafana, CloudWatch) and act on alerts
• Identify performance bottlenecks and work with senior engineers to implement optimizations
• Perform capacity monitoring and report disk, CPU, and memory trends as inputs to capacity planning
• Work assigned US day shift (EST/CST 8 AM – 6 PM) or US night shift (EST/CST 6 PM – 6 AM) rotations to provide 24/7 operational coverage including weekend rotation as required
• Act as the primary Linux operations contact during assigned shift for incident response, change execution, and escalation management
• Follow runbooks and standard operating procedures (SOPs) for all operational activities and maintain shift logs with current server and service status
• Create and maintain runbooks, SOPs, knowledge base articles, and operational checklists in Confluence
• Track tasks, incidents, and project work in JIRA with accurate and timely status updates
• Collaborate with network, storage, security, and application teams to resolve cross-functional issues
• Participate in team meetings, sprint reviews, and operational planning sessions
• Participate in on-call rotation and provide support for critical systems as needed

Qualifications:

The requirements listed are representative of the knowledge, skill, and/or ability required. Reasonable accommodations may be made to enable individuals with disabilities to perform the primary functions.

• 5–8 years of progressive hands-on experience in Linux/Unix system administration in an enterprise environment
• 2+ years in a senior or lead operational role with shift-based responsibilities
• Demonstrated experience managing Linux servers in production environments at scale
• Strong hands-on experience with Ansible Automation Platform (AAP) including playbook execution and operational automation
• Working experience with Red Hat Satellite for patch deployment and content lifecycle management
• Hands-on experience with AWS Linux EC2 instances including basic instance operations, snapshots, and security group management
• Demonstrated experience implementing and maintaining CIS benchmarks and security baselines across enterprise Linux systems
• Extensive experience with enterprise Linux patching programs including change management, patch validation, and emergency patching procedures
• Working experience with ITSM platforms such as ServiceNow for incident, problem, and change management
• Proficiency with collaboration and project management tools including JIRA and Confluence
• Ability to work US day shift (EST/CST 8 AM – 6 PM) or night shift (EST/CST 6 PM – 6 AM) on a rotating or fixed schedule including weekends as required
• Excellent problem-solving abilities and analytical thinking skills
• Strong written and verbal communication skills with ability to produce clear shift handover notes and operational documentation
• Ability to multitask and prioritize effectively in a fast-paced operational environment

Technical Skills:

Required Core Skills:

• Advanced hands-on proficiency in Red Hat Enterprise Linux administration and troubleshooting
• Strong knowledge of Linux internals including kernel management, systemd, networking stack, storage subsystems, and filesystem management
• Hands-on experience with Ansible Automation Platform (AAP) for operational task automation and playbook execution
• Proficiency with Red Hat Satellite for patch deployment, content views, and lifecycle management
• Strong experience with Linux patching and patch management including:
• Enterprise-scale patch deployment using Red Hat Satellite and Ansible
• Patch testing and validation in non-production environments
• Emergency and zero-day vulnerability patching procedures
• Kernel patching strategies and post-patch system validation
• Patch rollback and recovery procedures
• Compliance reporting and audit trail maintenance
• AWS Systems Manager Patch Manager for cloud-based patching
• Experience implementing CIS benchmark standards and security hardening including:
• CIS RHEL/Ubuntu/Amazon Linux benchmark implementation (Level 1 and Level 2)
• Automated compliance scanning using OpenSCAP, Lynis, or similar tools
• Remediation of CIS benchmark findings and exceptions management
• Security baseline enforcement using Ansible and configuration management
• Security audit preparation and response
• Proficiency with AWS Linux EC2 including instance management, AMI operations, snapshots, launch templates, and Amazon Linux/RHEL on AWS
• Hands-on experience with log management and analysis tools (rsyslog, journald, ELK Stack, Splunk, CloudWatch)
• Proficiency with monitoring solutions (Nagios, Prometheus, Grafana, CloudWatch) for alert management and performance monitoring
• Strong knowledge of LVM, NFS, and Linux storage management
• Proficiency with ITSM tools:
• ServiceNow for incident management, problem management, change management, and CMDB
• JIRA for task management, project tracking, and agile workflows
• Confluence for documentation, knowledge management, and runbook maintenance
• Strong networking knowledge (TCP/IP, DNS, DHCP, routing, firewalls)
• Proficiency in scripting (Bash, Python) for operational automation and task scripting

Additional Technical Skills:

• Familiarity with Terraform or CloudFormation for infrastructure-as-code support tasks
• Experience with backup solutions (Veeam, AWS Backup, snapshots)
• Experience with AMI creation, customization, and lifecycle management in AWS
• Knowledge of high-availability configurations (Pacemaker, Corosync)
• Deep knowledge of containerization technologies (Docker, Podman)
• Experience with version control systems (Git, GitLab, GitHub)
• Knowledge of package management (RPM, YUM, DNF) and repository management
• Understanding of security frameworks and compliance standards (CIS benchmarks, STIG, NIST)
• Experience with security scanning tools (OpenSCAP, Nessus, Qualys, Lynis)
• Knowledge of virtualization technologies (VMware, KVM)

Education and/or Experience:

• Minimum: Bachelor’s degree in computer science, Information Technology, or related field, or equivalent combination of education and experience
• 5–8 years of relevant hands-on Linux system administration experience required
• 2+ years of hands-on experience with Ansible Automation Platform required
• 2+ years of hands-on experience with AWS Linux EC2 and cloud infrastructure required
• 2+ years of working experience with Red Hat Satellite preferred
• Demonstrated experience executing Linux patching programs and supporting disaster recovery procedures required
• Proven experience implementing CIS benchmarks and security hardening across Linux environments required
• Working experience with ITSM tools (ServiceNow, JIRA, Confluence) for ticket management and documentation required
• Availability and willingness to work US day and/or night shift rotations including weekends required
• Red Hat Certified System Administrator (RHCSA) or Red Hat Certified Engineer (RHCE) strongly preferred
• AWS Certified SysOps Administrator or AWS Certified Solutions Architect – Associate strongly preferred
• ITIL Foundation certification a plus
• CompTIA Linux+ or Security+ a plus