# System Administration > Selected Engineer ApS work demonstrating System Administration — the achievements that prove it. - [Designed, deployed, and maintained 10 PostgreSQL and MS SQL servers on Ubuntu Linux VPS, ensuring optimal server performance and reliability.](https://data.engineer.company/portfolio/designed-deployed-and-maintained-10-postgresql-and-ms-13/) - [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.](https://data.engineer.company/portfolio/enhanced-data-security-by-implementing-1-000-rbac-14/)