Rakuten Cloud Platform Engineer, CICD Factory Department

About The Role

Job Description: About Organization Rakuten Symphony is at the forefront of revolutionizing the telecommunications industry, building the future of mobile networks with innovative, cloud-native, and Open RAN solutions. Our mission is to empower operators globally to deliver cutting-edge services efficiently and at scale. Job Duties Kernel-Level Optimization: Conduct deep-dive performance tuning (sysctl, tuna, /proc) to optimize RHEL for real-time (RT) workloads. RAN Workload Tuning: Configure and tune vCU/vDU components, implementing CPU isolation (isolcpus), IRQ affinity, and NUMA alignment to achieve deterministic performance. Network Acceleration: Optimize packet processing using DPDK and SR-IOV to bypass kernel bottlenecks for high-throughput RAN traffic. Advanced Troubleshooting: Lead Root Cause Analysis (RCA) for high-severity incidents using advanced tracing tools (ftrace, trace-cmd, perf). Automation & Hardening: Develop complex Ansible playbooks to automate kernel hardening and performance profile deployments across large-scale clusters. Lifecycle Management: Manage vulnerability patching, OS upgrades, and hardware-software interaction (Intel RDT, CAT, BIOS-level tuning). Virtualization: Expert management of KVM/QEMU, Red Hat OpenShift Virtualization, and containerized vDU pods within Kubernetes. Technical Skills & Tools Core: Kubernetes, Linux (RHEL 8/9, Rocky Linux), Docker, Helm, Git Hardware: Supermicro, Dell iDRAC, HP Automation: Ansible, Python, Shell Monitoring/Diagnostics: top, htop, vmstat, iostat, pqos, ftrace, perf Certifications: RHEL, CKA (Certified Kubernetes Administrator) Minimum Qualifications Experience: 8–12 years of relevant experience in telecommunications infrastructure engineering or SRE, with a proven track record in large-scale, complex environments. Kubernetes & Virtualization: Deep knowledge of bare-metal Kubernetes deployments and virtualization in development/production environments. Networking: Expertise in host-level networking, DNS/DHCP architecture, TLS management, load balancing, and advanced container networking. SRE Practices: Proven application of SRE principles, including major incident leadership, capacity/scalability strategy, and advanced change management. Security: Strong architectural knowledge of security hardening, RBAC models, pod security mechanisms, and secret management. Technical Depth: In-depth knowledge of process scheduling (SCHED_DEADLINE, SCHED_FIFO), memory management, and I/O schedulers. Languages: English (Overall - 3 - Advanced)