Linux System Administrator

Linux Systems Administrator / Technical Operations Engineer

Location: Vadodara (HQ) | Full-time, On-siteExperience: 3–5 yearsAbout the RolePhonon is looking for a hands-on Technical Operations Engineer to own one or more of the aspects related to our systems including: security, reliability, scalability and cost efficiency of our technology infrastructure.The role covers CloudOps, TechOps, DevOps, SecOps and FinOps, spanning our predominantly AWS-based cloud environment, Linux/network infrastructure and SIP/VoIP telephony platforms.

The role will also lead resolution of complex cloud and production support issues.Key ResponsibilitiesOwn and operate highly available, secure and scalable AWS infrastructure.Manage Linux, networking, VPNs, firewalls, load balancers and telephony infrastructure.Own Asterisk, FreePBX, OpenSIPS, SIP/RTP, SIP trunks, IVRs, diallers and hosted PBX environments.Drive DevOps, CI/CD, Infrastructure as Code, containerisation and operational automation.Own infrastructure security, vulnerability management, patching, IAM, hardening, backup/DR and ISO 27001 readiness.Establish monitoring, alerting, incident management and RCA practices.Drive FinOps, including AWS utilisation, rightsizing and cloud cost optimisation.Lead complex production incidents and cloud/infrastructure support escalations.Lead and mentor the Cloud/Technical Operations team.Technology StackLinux & Networking: RHEL/CentOS/Ubuntu, TCP/IP, DNS, routing, NAT, VPN, firewalls, SSL/TLS, load balancingCloud: AWS – EC2, VPC, RDS, S3, ELB/ALB, Auto Scaling, Route 53, CloudFront, IAM, CloudWatch, CloudTrail, Lambda, SNSTelephony: Asterisk, FreePBX, OpenSIPS, SIP, RTP, SIP Trunking, IVR, Diallers, Hosted PBXDevOps: Terraform, CloudFormation, Ansible, AWS CLI, Docker, Kubernetes, Git, Jenkins/GitLab CI/GitHub ActionsObservability: Prometheus, Grafana, Loki, ELK/EFK, Nagios, CloudWatchSecurity: IAM/RBAC, encryption, secrets management, vulnerability management, infrastructure hardening, ISO 27001Candidate Profile3-5 years across cloud infrastructure, Linux, networking, DevOps and technical operations.Strong hands-on experience managing AWS production environments.Strong Linux and networking fundamentals with experience operating high-availability systems.Telecom/SIP/VoIP experience is strongly preferred.Strong troubleshooting skills across cloud → network → Linux → application → telephony.Experience leading technical teams and handling critical production incidents.Preferred Certifications: RHCE and CCNA; AWS certification is an advantage.We are looking for a hands-on technology operations owner who can troubleshoot critical infrastructure issues while building a secure, reliable, scalable and cost-efficient operations function.