About the Company
We provide advanced infrastructure for financial trading, including high-performance trading platforms.
Position Summary
We’re looking for a dependable and experienced Intermediate Linux System Administrator with at least five years of hands-on experience managing Linux environments in production. The ideal candidate will be highly skilled in Red Hat-based Linux systems and have solid experience with managing Kubernetes clusters—including deployment, upgrades, and maintenance. You should be well-versed in system provisioning, security hardening, DNS, and general best practices in system administration. This role involves independent learning, ensuring production stability, and participating in an on-call rotation with occasional weekend responsibilities.
Key Responsibilities
Manage, monitor, and maintain Linux servers (primarily RHEL or similar) across production and development environments.
Deploy, manage, troubleshoot, and upgrade Kubernetes clusters both on-premises and in the cloud.
Provide support during scheduled on-call shifts, including after-hours response.
Participate in planned weekend maintenance activities for updates, patching, and critical deployments.
Diagnose and resolve system issues with minimal supervision, escalating when necessary.
Keep system documentation up to date, including processes and incident records.
Collaborate with various teams to uphold system reliability and compliance.
Continuously learn and adopt new technologies and tools.
Communicate clearly and professionally in English, both verbally and in writing.
Required Skills and Experience
3–5 years of hands-on Linux system administration experience.
Strong understanding of RHEL-like distributions (RHEL, Rocky Linux, CentOS).
Practical experience managing Kubernetes clusters, including deployment, updates, and troubleshooting.
Proven ability to work independently, learn quickly, and perform under pressure.
Excellent communication skills in English (spoken and written).
Willingness to be part of an on-call support rotation and work occasionally on weekends.
Preferred Qualifications
Kubernetes certification (e.g., CKA) or working toward certification.
RHCSA or RHCE certification.
Experience with tools like Ansible, Puppet, Terraform, or Helm for system configuration.
Familiarity with CI/CD workflows and container technologies such as Docker and Helm.
Benefits
Enrollment in the Kanto IT Software Health Insurance Association.
Defined-contribution retirement plan (similar to a 401(k)) after the probation period.
Group life insurance through SBI (post-probation).
Major illness insurance from Sumitomo Seimei (post-probation).
Reimbursement for qualifying certifications.
Casual office attire.
Support for self-guided learning and development.
English-speaking workplace environment.
Office with direct access to Roppongi-Itchome Station (Namboku Line).