$ cat /etc/motd
Notes from the infrastructure side of the terminal.
Susai's Blog is a working engineer's notebook on Linux, Oracle Cloud Infrastructure, and Ansible — practical write-ups distilled from running enterprise platforms, disaster recovery, and automation in production.
ls ~/blog/posts
Latest posts
~/blog/linux
Linux Fundamentals Every Engineer Should Master
The filesystem hierarchy, processes, permissions, and the handful of commands that solve 80% of day-to-day problems on any distribution.
~/blog/linux
Managing Services with systemd: A Practical Guide
Units, targets, journald, and writing your own service files — how modern Linux actually boots and keeps your applications running.
~/blog/oracle-cloud
Oracle Cloud Infrastructure: Core Concepts Explained
Regions, availability domains, compartments, VCNs, and IAM — the mental model you need before deploying anything on OCI.
~/blog/oracle-cloud
Designing Disaster Recovery on OCI Across Regions
Cross-region DR patterns on Oracle Cloud: replication options, Full Stack DR, DNS steering, and how to think about RTO and RPO.
~/blog/ansible
Ansible from Zero: Inventories, Playbooks, and Idempotency
Why agentless automation works so well, how a playbook is structured, and the idempotency mindset that separates scripts from automation.
~/blog/ansible
Patching Linux Fleets at Scale with Ansible
Serial batches, health checks, reboots, and rollback thinking — a repeatable pattern for OS patching across dozens of servers.
whoami
About Susai
I'm Susai Selvaraj — a Technical Lead and Cloud Architect working on large-scale enterprise infrastructure. Originally from Tamil Nadu, India, and currently based in Riyadh, Saudi Arabia, I lead cloud and disaster-recovery engineering for national-scale managed services programmes.
My day-to-day work spans Oracle Cloud Infrastructure architecture and landing zones, Microsoft enterprise platforms (Exchange, Active Directory, Entra ID, Intune), network and security engineering with the Fortinet stack, and infrastructure-as-code with Terraform and Ansible. I've designed and run cross-region DR programmes covering identity, messaging, DNS, databases, and full-stack failover orchestration.
This blog is where I turn production experience into generic, reusable knowledge — the posts are written to be useful on any environment, not just mine. If a write-up here saves you one late-night incident call, it has done its job.
Quick facts
- roleTechnical Lead & Cloud Architect
- focusOCI, DR orchestration, enterprise platforms
- locationRiyadh, Saudi Arabia
- originTamil Nadu, India
- sitesusaiselvaraj.com
Toolbelt
- Linux
- OCI
- Ansible
- Terraform
- Exchange
- Active Directory
- Entra ID
- Intune
- FortiGate
- PostgreSQL
- DNS & PKI
- Bash / PowerShell