System Administration
Keeping the lights on
Day-to-day care of servers, mail, accounts and updates, so the things everybody relies on stay boring.
Selected work demonstrating this service.
- Designed, deployed, and maintained 10 PostgreSQL and MS SQL servers on Ubuntu Linux VPS, ensuring optimal server performance and reliability.
- Enhanced data security by implementing 1,000 RBAC rules for developers, application instances, PostgreSQL, MS SQL, and other Linux servers, preventing unauthorized access; documented with Ansible automation.
- Managed 30 Ubuntu Linux VPS instances, implementing disaster recovery strategies and ensuring optimal network configurations.
- Prevented security breaches by leading access management initiatives, utilizing M365, 1Password, Red Hat SSO, and OKTA SSO.
- Managed and troubleshooted 8 WireGuard VPN and IPSEC VPN connections, ensuring secure communication across Google Cloud and Linux systems.
- Administered network infrastructure for over 1,000 servers, ensuring optimal system deployment, security, and troubleshooting.
- Configured and deployed 1,000 Wi‑Fi routers, improving network accessibility and performance for clients.
- Administered 100 Bare Bone servers, physical networks, and IP telephony systems, ensuring robust infrastructure for company growth.
- Administered 40 websites on Ubuntu Linux hosting servers with Apache and Nginx, ensuring high availability and performance.
- Provided round‑the‑clock 24/7 infrastructure support for an IPTV/OTT streaming platform, administering ~1,000 servers plus client‑owned systems for global customers in China, the US and Germany.
- Ensured uninterrupted delivery of IPTV streaming signals between suppliers and clients, monitoring and maintaining the streaming network and IP telephony around the clock.
- Planned and implemented new infrastructure functionality for internal and external systems, building solutions durable enough to still run years later with minimal change.
- As one of the first hires, designed and built the entire core infrastructure and supporting processes from scratch for a green‑energy SaaS startup, laying the foundation for rapid growth.
- Integrated a company‑wide password‑management system, strengthening security and streamlining access control.
- Built the company's own infrastructure as 19 Ansible playbooks and 34 roles across 12,065 lines of YAML, converging a live host to a declared state with every play idempotent.
- Ran the whole company on one 512 MB single‑core host — a git forge, a web server serving seven domains, Tor, two alternate‑protocol servers, backups and intrusion banning — by treating 464 MB of usable memory as the binding architectural constraint.
- Hardened SSH to 24 asserted directives with three‑stage validation — the candidate file, the assembled config, then the daemon's own read‑back — after the read‑back caught the running server silently overriding two of the twenty‑four.
- Proved the intrusion‑banning path end to end on every hardening run by banning a reserved test address, reading the resulting kernel rule and unbanning in a guaranteed cleanup block, so a jail that stops working fails a run instead of reporting healthy.
- Verified firewall rules by position rather than presence, reading the numbered rule list and the live packet‑filter chain, because a rule that exists is not a rule any packet reaches.
- Built encrypted off‑host backups on restic with retention pruning, an integrity check and a monthly automated restore drill, then audited the recovery position and wrote down the gaps rather than leaving them to be found during an incident.
- Built dead‑man's‑switch monitoring that pings only while memory and disk are healthy, so a degraded host raises an alert by going silent — and caught six variable names saying "free" where the check correctly measured "available", an order of magnitude apart on a 464 MB box.
- Reconciled a 20‑record DNS zone declaratively against the Cloudflare API with separate audit and BIND‑export entry points, and turned the CDN proxy back off on privacy grounds after building it.
- Cut systemd sandbox exposure across every unit this platform installs — a dead‑man's‑switch service from 9.6 UNSAFE to 1.5, an internet‑facing git forge from 8.3 EXPOSED to 1.5 — and added a converge‑time parser check after finding a misspelled directive silently ignored in three unit templates.
- Built seven read‑only reporting roles that render a live host to Markdown — facts, access, git, metrics, traffic, security and provider inventory — under a rule that no number is printed the run did not measure.
- Deployed the company's own git forge on Soft Serve, private by default with no web panel and its SSH port bound to loopback behind a jump host, and made the landing page in front of it a build artefact of the main site rather than a hand‑kept copy.
- Rehearsed the forge‑side CI hook and found two defects unreachable by reading the file: a fallback that put an unresolvable argument on the hook's input, and git's own environment variable following the gate into the checkout and turning 19 tests red.