Senior Linux Systems Administrator

RapidFort, Inc.; United States; Remote; USD 125,000 - 165,000; Full time

Job summary

RapidFort, Inc. is seeking a senior, hands-on systems engineer to own operations of our Linux-based fleet, both on-prem and cloud. You will keep the systems reliable, secure, and well-documented, plan changes, and lead incident response when things break.

This is a hands-on senior individual-contributor role with responsibility for technical execution across disks, kernels, routing, firewalls, and DNS. You will work with a remote team to replace manual tasks with automation, write Ansible roles

Qualifications

• Typically eight or more years administering Linux servers in production with root responsibility.
• Solid working knowledge of Debian and other Linux distributions.
• Experience with container runtimes and orchestration like Docker and Kubernetes.
• Experience with configuration management tools (Ansible, Terraform) and GitOps practices.
• Strong networking knowledge including DNS, routing, and firewall tools.
• Familiarity with system security, hardening, and patch management.

Responsibilities

• Operate a fleet of remotely managed Linux servers and perform OS/kernel upgrades.
• Maintain consistent configurations and correct drift across environments.
• Manage AWS resources (EC2, S3) and related services.
• Run self-hosted development services and troubleshoot CI pipelines.
• Diagnose production issues using logs and metrics to find root causes.
• Improve monitoring/alerts to catch issues early without noise.
• Collaborate with developers, IT, and hardware vendors across teams.
• Document changes and automate repetitive tasks with reliable scripts and playbooks.

Skills

Linux administration

Debian

KVM/QEMU

Docker

Kubernetes

Git

Ansible

AWS

Networking

TLS certificates

Tools

Terraform

GitOps

Job description

Experience:8+yearsofrelevanthands-onexperience

BaseSalary:$125,000–$165,000annually,plusequityandbenefits

ABOUTRAPIDFORT

RapidForthelpsenterprisesandgovernmentorganizationsreducesoftware

supply-chainriskthroughhardenedcontainerimages,runtime-based

attacksurfacereduction,andautomatedvulnerabilityremediation.We

ownandoperatetheinfrastructurethatsupportsourengineeringteams

ABOUTTHEROLE

virtualmachinesandcontainersthatrunonthem,thenetworksthat

connectthemtoeachotherandtoourstaff,self-hosteddevelopment

Youwillkeepthesesystemsreliable,secureanddocumented,planand

carryoutchangestothem,andleadtheresponsewhensomethingbreaks.

Thisisahands-onseniorindividual-contributorrolewithdirect

responsibilityfortechnicalexecution.Weneedsomeonewhoseknowledge

runsfromdisksandkernelsuptoroutingtables,firewallsandDNS.

RESPONSIBILITIES

• Operate a fleet of remotely managed physical Linux servers and the operating system and kernel upgrades, tracking exceptions, and moving systems off releases that reach end of life.
• Keep configurations consistent, and find and correct configuration drift.
• Manage our resources in AWS, mainly EC2 and S3.
• Run the self-hosted development services, including GitLab, CI Troubleshooting and incident ownership.
• Independently diagnose production problems involving CPU, memory, and other critical issues, using logs, metrics, and command‑line tools to find root causes and confirm that a fix worked.
• Monitor the systems, and improve monitoring and alerting so that problems are caught early without needless noise; corrective actions keep a problem from recurring.
• Work with developers, IT, data‑center staff and hardware vendors when a problem crosses system boundaries.
• Escalate when needed, with clear findings, supporting evidence, automation and configuration management where it makes operational work more reliable or simpler.
• Write and maintain Ansible roles and playbooks to the team’s standards.
• Replace repetitive manual tasks with reliable, maintainable automation.
• Keep configuration and automation in Git, test changes, and make changes through merge requests, review and automated deployment rather than editing live systems.
• Own access control and security: SSH keys and hardware security keys, network access policies, least privilege, security baselines, timely patching, vulnerability scanning, audits of exposed services, and software supply‑chain risk.
• Run the backups and prove that they restore.
• Plan changes and maintenance with a written procedure that gives the steps, how to check the result, and away back records and troubleshooting notes, and review other engineers’ changes. Windows.

REQUIREDEXPERIENCEANDSKILLS

• Typically eight or more years administering Linux servers in production with root responsibility, including physical hardware and not only cloud instances, with recent hands‑on responsibility for operations and troubleshooting. Solid working knowledge of most of the following.
• Strong experience with Debian and other Linux distributions.
• Resource control and diagnosis: cgroups v2, memory management and the Both systemd and SysV init.
• Linux routing: multiple routing tables, policy routing with ip rule, source‑based routing, and routing between sites.
• Traffic shaping with tc: queueing disciplines (HTB, fq_codel, cake), classification with tc filters or firewall marks, and ingress shaping through ifb.
• nftables, including sets, maps and connection tracking, and enough iptables to read and merge older rule sets.
• DNS and DHCP: unbound as a validating recursive resolver with local DNS, and debugging name resolution with dig.
• ZFS in depth: pool layout, datasets and zvols, snapshots, send and recover damaged pool.
• mdadm RAID, LVM, ext4 and XFS, filesystem repair, SSD caching such as write persistence.
• KVM/QEMU or Xen, LXC and Docker, and enough Kubernetes to debug a that restores work.
• S3: bucket policies, versioning, lifecycle rules and encryption.
• IAM roles and policies written to the principle of least privilege.
• Git: branching, merging and conflict resolution in merge‑request workflow, without rewriting or destroying history.
• GitOps and infrastructure as code: configuration that lives in Git and is applied automatically after review, drift detection, and OpenTofu or Terraform. Experience with a comparable configuration‑management tool.
• Host hardening, least privilege, firewall design, and finding and closing services that are exposed by mistake.
• TLS certificates and their renewal, and safe handling of secrets.
• Patch management, vulnerability scanning, software supply‑chain risk, and investigating incidents from logs.
• Expert Bash: robust scripts with sound error handling, quoting, traps, and commands run over SSH, which you can write, troubleshoot and maintain in production on your own.
• A record of personally resolving complex technical problems, following through on the corrective actions.
• Clear, precise written English for change plans, incident reports, reviews, tickets and documentation.
• The ability to work independently within a remote team.

PREFERRED

• Server hardware: IPMI, iDRAC, iLO and other BMC consoles, RAID and diagnosing PCIe devices and their drivers and firmware from kernel logs.
• Physical data‑center work, and working with data‑center remote hands.
• GPU servers, NVIDIA drivers and CUDA environments, and infrastructure.
• Other virtualization platforms, such as Proxmox or VMware.
• SAN and NAS storage, and multipathing.
• Jenkins or other build farms, and caching mirrors or proxies for apt, PyPI, npm or Maven.
• Infrastructure that supports SOC2 or ISO27001 controls.
• Debian and its derivatives.
• Other cloud providers, such as Linode.