Senior Linux Systems Administrator

Experience:8+yearsofrelevanthands-on experience

Base Salary:$125,000–$165,000annually,plusequityandbenefits

Rapid Forthelpsenterprisesandgovernmentorganizationsreducesoftware

supply-chainriskthroughhardenedcontainerimages,runtime-based

attacksurfacereduction,andautomatedvulnerabilityremediation.

We

ownandoperatetheinfrastructurethatsupportsourengineeringteams

virtualmachinesandcontainersthatrunonthem,thenetworksthat

connectthemtoeachotherandtoourstaff,self-hosteddevelopment

Youwillkeepthesesystemsreliable,secureanddocumented,planand

carryoutchangestothem,andleadtheresponsewhensomethingbreaks.

Thisisahands-onseniorindividual-contributorrolewithdirect

responsibilityfortechnicalexecution.

Weneedsomeonewhoseknowledge

runsfromdisksandkernelsuptoroutingtables,firewallsandDNS.

• 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 Git Lab, 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.

• 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, , 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, file system repair, SSD caching such as write persistence.
• KVM/QEMU or Xen, LXC and…