▍ DevOps Engineer @ xCloud
Hi, I'm Md. Nazmus Sadat.
DevOps Engineer
I automate, harden and keep production web infrastructure running at scale.
servers operated
incidents resolved
fleet uptime
on-call coverage
I'm a DevOps Engineer who lives in the terminal and automates his way out of it.
I run production web infrastructure for a managed cloud hosting platform — provisioning, deployment pipelines, performance tuning, hardening and incident response across a fleet of Linux VPS nodes serving hundreds of customer workloads.
Day to day that means Nginx and OpenLiteSpeed vhosts, PHP-FPM and Node/PM2 services, Docker workloads, MySQL/MariaDB and Redis, Cloudflare edge config, systemd units and cron pipelines. When something breaks at 2am I find root cause from the logs, not from guesswork.
The part I care about most is durability: a fix that survives a panel regeneration, a config that a teammate can read, and a runbook so the next person doesn't have to relearn it. Toil that repeats gets scripted.
- Focus
- Linux infrastructure, automation & reliability
- Stack
- Linux · Nginx/OLS · Docker · MySQL · Redis · Bash
- Approach
- Investigate → confirm → backup → change → verify
- Status
- DevOps Engineer @ xCloud
The toolkit I reach for under pressure.
- ›Ubuntu / Debian
- ›systemd units & drop-ins
- ›Resource & OOM tuning
- ›Kernel / sysctl
- ›Process & memory forensics
- ›Nginx
- ›OpenLiteSpeed / LiteSpeed
- ›PHP-FPM pool tuning
- ›Node.js · PM2
- ›Reverse proxies & upstreams
- ›Docker & Compose
- ›Vultr · Hetzner · DigitalOcean
- ›AWS (EC2 · S3 · Route 53)
- ›Image builds & registries
- ›Provisioning & snapshots
- ›Git · GitHub Actions
- ›Zero-downtime deploys
- ›Bash & Python tooling
- ›Cron & Supervisor pipelines
- ›Config-as-code / includes
- ›MySQL / MariaDB
- ›Redis (ACLs · object cache)
- ›Backups & restores
- ›Migrations at scale
- ›Query & cache tuning
- ›DNS · SSL/TLS · Let's Encrypt
- ›Cloudflare (proxy · origin certs)
- ›UFW · fail2ban · WAF rules
- ›tcpdump / traceroute / mtr
- ›Malware IR & hardening
Where I've kept the lights on.
DevOps Engineer @ xCloud
June 2025 — Present- ▹Operate and troubleshoot a multi-tenant fleet of Linux VPS nodes (Nginx & OpenLiteSpeed) running hundreds of production customer workloads.
- ▹Own SEV-1 incident response end to end: PHP-FPM 502s, MySQL OOM crash-loops, TLS/origin-cert failures, cache and permission faults — diagnosis from logs to durable fix.
- ▹Harden services against recurrence — systemd OOM protection drop-ins, right-sized FPM/worker pools, firewall and WAF rules, per-tenant Redis ACLs and database isolation.
- ▹Ship regeneration-proof configuration as code using persistent vhost include layers, so platform-generated configs never overwrite custom tuning.
- ▹Automate repeat toil with Bash tooling and cron/supervisor pipelines; maintain deployment workflows for Git-backed PHP, Node and Docker sites.
- ▹Write the team's incident runbooks and post-mortems, turning one-off fixes into repeatable, documented procedures.
Implementation Engineer @ SouthTech Limited
2023 — 2025- ▹Deployed and configured customer environments across hosting, email and DNS.
- ▹Ran server and site migrations with post-migration verification and rollback plans.
- ▹Built internal documentation and runbooks for recurring incidents.
Real incidents — problem, diagnosis, durable fix.
Sites across a shared VPS intermittently 502'd with DB-connection errors; mysqld was being OOM-killed repeatedly and stayed down until a manual restart.
The database was the victim, not the hog: one PHP-FPM pool with an oversized min_spare pinned 50+ idle workers and thrashed swap until the kernel killed the lowest-priority process. The stock unit's Restart=on-abort never restarts after a SIGKILL, so it never came back on its own.
Right-sized the pool's pm.* values and graceful-reloaded FPM, then shipped a systemd drop-in with OOMScoreAdjust=-600, Restart=on-failure and a start-limit breaker — the DB now survives the spike and self-heals. Rolled the same drop-in across the fleet as a standard.
B.Sc. in Computer Science & Engineering
2010-2014Ahsanullah University Of Science & Technology
Foundations in networking, operating systems, and databases that underpin my infrastructure work today.
$ ./say-hello.sh
Got infrastructure to tame, or a DevOps role to fill? Let's talk.
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