Senior Linux System Administrator

Title:                   Senior Linux System Administrator (L3)

Location:            Irving, TX (Onsite)

Type:                   Fulltime (Tata Consultancy Services)

Role Summary

Seeking a hands-on L3 Linux Administrator to own stability, availability, and performance across large-scale Linux environments. The role demands deep troubleshooting skills, strong exposure to Veritas Clustering (VCS), SAN/NAS storage, and close coordination with data center teams for hardware incidents. The ideal candidate will work independently, lead incident resolution, and improve BAU operations through automation and best practices.

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Key Responsibilities

Linux Administration (L3)

·       Administer and troubleshoot RHEL, Oracle Linux, CentOS, SUSE in production.

·       Diagnose complex OS issues: kernel panics, boot/GRUB failures, filesystem corruption, resource contention (CPU/RAM/I/O/Network), SELinux/AppArmor denials.

·       Patch and upgrade OS at scale; manage package repositories and kernel updates with rollback strategies.

·       Implement and audit security hardening (firewalld/iptables, CIS benchmarks, PAM, sudo, SSH, auditd).

·       Manage system services (systemd), cron/timers, users/groups, sudoers, and system-wide configuration.

·       Veritas Cluster Server (VCS/InfoScale)

·       Install, configure, and administer VCS for HA/DR across multi-node clusters.

·       Create/maintain service groups, resources, dependency trees; configure LLT/GAB, I/O fencing, and quorum.

·       Integrate VxVM/VxFS (disk groups, volumes, file systems) with application failover.

·       Conduct DR drills, failover testing, and root cause analysis for cluster events.

·       Storage: SAN & NAS

·       Liaise with storage teams for LUN provisioning, zoning, masking; validate multipathing (DM Multipath/PowerPath).

·       Build and maintain filesystems (ext4/xfs/VxFS), mount policies, fstab and autofs.

·       Manage NFS/CIFS/SMB exports/mounts, permissions, quotas, and locking issues.

·       Troubleshoot pathing, latency, and I/O bottlenecks using OS, HBA, and array-side telemetry.

·       Data Center & Hardware Coordination

·       Coordinate with DC teams for racking/stacking, cabling, console access, and physical triage.

·       Diagnose hardware faults (CPU, memory, NIC/HBA, disks/RAID/SSD, backplane, PSU, fans) and firmware/BIOS alignment.

·       Raise and track OEM tickets (Dell/HP/IBM/Cisco), manage RMA, and oversee replacements and post-fix validation.

·       BAU Operations & Incident Management

·       Act as L3 escalation for P1/P2 incidents; drive bridge calls and lead technical recovery.

·       Perform deep-dive log analysis (journald, syslog, dmesg, audit logs, application logs).

·       Create/run SOPs/runbooks, maintain KB articles, and implement problem management (RCA, corrective actions).

·       Support on-call rotation and scheduled maintenance windows (change management, CAB, MOPs).

·       Networking (Host-Level)

·       Troubleshoot TCP/IP, routing, VLANs/bonding/teaming, MTU, host firewalls, DNS/DHCP, NTP/Chrony.

·       Collaborate with network teams on L2/L3 connectivity, load balancers, and firewall rules.

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Required Experience & Skills

·       8–12+ years in enterprise Linux system administration with proven L3 ownership.

·       Strong hands-on with VCS (Veritas Cluster Server), VxVM, VxFS, and HA/DR patterns.

·       Solid SAN/NAS experience: LUNs, zoning, multipath, NFS/SMB.

·       Demonstrated success working independently and leading during critical incidents.

·       Advanced troubleshooting: kernel, performance, storage, and cluster-level failures.

·       Scripting proficiency (Bash; Python preferred). Familiar with Ansible.

·       Familiarity with VMware/KVM and basic cloud (AWS/Azure/Linux in cloud) concepts.

·       Strong documentation discipline (SOPs, MOPs, RCAs) and ITIL-aligned processes