Senior Systems Administrator

Job Description

Sharetru is a secure managed file transfer (MFT) platform trusted by organizations with high security, compliance, and availability requirements. We operate infrastructure across multiple data centers and network providers while supporting customers subject to SOC 2, HIPAA, and FedRAMP-aligned controls.

Our environment is Linux-first, security-focused, and built for reliability at scale. This role is for someone who thrives in complex systems, values automation, and understands that production stability matters more than clever shortcuts.

Why This Role Matters

This role is critical to the reliability and security of Sharetru’s platform. The systems you manage directly support customer data, compliance commitments, and business continuity. We’re looking for someone who understands that good infrastructure is quiet, boring, and deliberate.

What You'll Do

As a Senior Systems Administrator, you will be responsible for the design, operation, hardening, and reliability of our Linux infrastructure across multiple networks and data centers including:

• Administer and harden Red Hat Enterprise Linux/Rocky Linux systems across production, staging, and internal networks
• Operate infrastructure spanning multiple data centers, including segmented networks, DMZs, and private backend tiers
• Manage and secure services including:

• Apache / PHP-FPM
• SFTP / FTPS (ProFTPD or equivalent)
• MySQL / Percona (including Galera clusters and proxies)
• HAProxy / reverse proxies / WAF-style architectures
• Design and maintain high-availability and fault-tolerant systems
• Implement and maintain security controls:
• SELinux (enforcing, custom policies)
• iptables / nftables / ipset
• TLS hardening (FIPS-aware where applicable)
• MFA, access controls, and least-privilege enforcement
• Support and contribute to compliance efforts (SOC 2, HIPAA, FedRAMP-aligned controls), including evidence collection and control validation
• Automate system configuration and maintenance using Ansible, shell scripting, and/or Python
• Troubleshoot complex production issues across OS, network, and application layers
• Participate in change management, incident response, and root cause analysis
• Collaborate closely with engineering, support, and compliance teams to keep systems stable, secure, and auditable
• Log into systems, read logs, understand packet flow, and know why something is not working as expected.

Requirements

• 7+ years of professional Linux systems administration experience
• Strong experience with RHEL-based distributions (RHEL, Rocky, CentOS)
• Deep understanding of Linux Networking (routing, firewalls, NAT, VPN concepts), system performance and troubleshooting, and filesystems, storage, and backups
• Proven experience securing Linux systems in regulated environments
• Experience with SELinux beyond permissive mode
• Experience with iptables/nftables/ipset in production
• Strong knowledge of TLS, certificates, and cryptography basics
• Experience operating high-availability systems (clusters, failover, redundancy)
• Solid scripting skills (Bash required; Python a strong plus)
• Familiarity with configuration management (Ansible preferred)

Nice to Have (But Not Required)

• Experience with FedRAMP or NIST 800-53–aligned environments
• Experience with Percona XtraDB Cluster / Galera / ProxySQL / HAProxy
• Experience in multi-datacenter or SaaS environments
• Exposure to Proxmox, VMware, or similar virtualization platforms
• Experience building or maintaining internal admin tooling

Operational & Compliance Experience

• Experience supporting environments subject to SOC 2, HIPAA, or PCI.
• Understanding of change management, access controls, and audit requirements
• Comfortable producing documentation and evidence for auditors
• Ability to make changes carefully in shared, customer-impacting systems

Professional Expectations

• Strong troubleshooting and critical thinking skills
• Comfortable working independently and owning systems end-to-end
• Clear communicator who documents decisions and changes
• Security-first mindset — you understand that “it works” is not enough
• Calm under pressure during incidents and outages

Benefits

• Health Care Plan (Employer-paid Medical, Dental, & Vision)
• Retirement Plan (401k, IRA)
• Paid Time Off (Vacation, Sick Time & Public Holidays)
• Work From Home
• Reimbursement for mobile phone and home internet
• Company-issued computer and technology needed for your role