Tamas Rebeli

About team

Experience

2025–now

CEO/Co-Founder/Senior System Engineer; Sysagnostic

2018–now

Course Instructor; Webváltó Kft.

Courses in PostgreSQL Administration, Linux Administration

2023–2024

PostgreSQL System Architect (contractor); Allianz Technology SE

Design and execution of PostgreSQL mass migration in Microsoft Azure

Azure Database for PostgreSQL Flexible Server; Ansible, Terraform, GitHub Actions

2021–2022

PostgreSQL System Architect (contractor); Hungarian Central Statistical Office

PostgreSQL HA cluster design and implementation

PostgreSQL; PgPool-II; Linux

2019–2022

PostgreSQL System Architect (contractor); Allianz Technology SE

PostgreSQL on-prem platform design and implementation

PostgreSQL; Ansible; New Relic; Red Hat Linux

2018–now

PostgreSQL Support Engineer (contractor); for various companies via Webváltó Kft.

Database support (on-call)

PostgreSQL, EnterpriseDB

2018–2019

Senior System Engineer (contractor); Erste Bank Hungary Zrt.

Infrastructure design and implementation on PSD2 project

Axway API Gateway, OpenSpan IAS and Gateway; Linux

2016–2017

Middleware System Administrator (contractor); Erste Bank Hungary Zrt.

Oracle Weblogic

2015–2016

System Engineer (contractor); T-Systems Magyarország Zrt.

Infrastructure implementation for a public sector project

Oracle API Gateway, OpenLDAP; Linux

2011–2016

Database Support Engineer; Webváltó Kft.

Emergency hotline support services (on-call)

Oracle RAC, Oracle DataGuard; Linux, HP-UX, AIX

2012–2014

System Engineer (contractor); Deutsche WertpapierService Bank AG

Infrastructure support

Linux, Oracle Database, Veritas Cluster

Languages

English: Bilingual
Hungarian: Native

Certifications

2023: Oracle Certified Professional Oracle Linux 8 System Administrator; Oracle
2023: Oracle Database 12c Administrator Certified Professional; Oracle
2023: Oracle Weblogic Server 12c Certified Implementation Specialist; Oracle
2022: Oracle Cloud Infrastructure Foundations 2021 Associate; Oracle
2022: EnterpriseDB Certified PostgreSL 13 Associate; EDB
2019: MikroTik Certified Security Engineer (MTCSE); MikroTik
Certification ID: 1905SE4060
2018: MikroTik Certified User Management Engineer (MTCUME); MikroTik
Certification ID: 1801UME1766
2018: MikroTik Certified Traffic Control Engineer (MTCTCE); MikroTik
Certification ID: 1810TCE1908
2018: MikroTik Certified Routing Engineer (MTCRE); MikroTik
Certification ID: 1810RE3044
2018: MikroTik Certified IPv6 Engineer (MTCIPv6E); MikroTik
Certification ID: 1810IPv6E3060
2016: MikroTik Certified Network Associate (MTCNA); MikroTik
Certification ID: 1607NA396
2016: MikroTik Certified Wireless Engineer (MTCWE); MikroTik
Certification ID: 1610WE057
2012: Oracle Enterprise Manager Certified Implementation Specialist (12c); Oracle

Education

2015

Post-graduate Degree, Technical Translator from English and Hungarian Languages; Budapest University of Technology and Economics, Faculty of Economics and Social Sciences

2010

MSc, Computer Science and Engineering; Budapest University of Technology and Economics, Faculty of Electrical Engineering and Informatics

Specialization in Infrastructure Design

Thesis: Performance analysis of distributed parallel tasks in grid architectures

Author's posts

Isolating resource consumption for PostgreSQL instances in Linux – Part 2

In Part 1, we have looked at some core systemd concepts, and general resource limit settings in Linux. Let’s put all of that to use by configuring isolation of resource consumption for PostgreSQL via systemd.

Isolating resource consumption for PostgreSQL instances in Linux – Part 1

In a traditional, on-premises enterprise environment, a single bare-metal server or virtual machine may host multiple PostgreSQL server instances. Even though they share the same machine, they often belong to different applications, projects or organizational units, and are required to be isolated in terms of utilizing system resources like RAM, CPU and disk I/O, usually for the purpose of business management.