Şenol Çolak, Developer in Berlin, Germany
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Şenol Çolak

Verified Expert  in Engineering

DevOps Engineer and Developer

Location
Berlin, Germany
Toptal Member Since
September 21, 2022

Şenol has worked in IT since 1993, developing software, creating and managing teams, and acquiring C-level experience. From a technical perspective, he defines himself as a good site reliability engineer (SRE). Şenol likes to create incredible and stunning technical solutions. There are still running systems he created decades ago, and the professionals he mentored are all in the industry.

Portfolio

Kubedo GmbH
Django, Python 3, Ansible, Ansible Tower, VyOS, Terraform, Linux...
German Edge Cloud
OpenStack, Kubernetes, Ceph, GitOps, Ansible, Ansible Tower
Nekkra UG
Node.js, Angular, HTML, PHP, JavaScript, CSS, Laravel, Vue, Redis, MongoDB...

Experience

Availability

Full-time

Preferred Environment

MacOS, Linux, Kubernetes, Cloud Computing, Python, Ansible, KVM/Qemu, OpenStack

The most amazing...

...thing I've built is a giveback platform called Açık Kaynak Fikirler (AKF), a community with 10,000+ subscribers. I send newsletters and mentor people there.

Work Experience

Chief Executive Officer

2022 - PRESENT
Kubedo GmbH
  • Created a company from scratch with ITSM and an inventory system. Hostbill, a CRM implemented with back-end services and product development.
  • Developed MVP for cloud management services. Automation and back-end configurations implemented.
  • Acquired new customers and implemented features. After the launch, we had eight paid customers.
Technologies: Django, Python 3, Ansible, Ansible Tower, VyOS, Terraform, Linux, IT Service Management (ITSM), Kubernetes, ITIL, Team Management, DevOps, Firewalls, Security, Infrastructure as Code (IaC), GitOps, OpenStack, Hypervisors, Docker, MySQL, Amazon Web Services (AWS), Cloud Computing, Architecture, Cloud, Continuous Deployment, HashiCorp, Ubuntu Linux, Proxy Servers, Python, VPN, Networking, Ubuntu, Back-end, IT Infrastructure, Ceph, NGINX, Scripting, Proxmox

Cloud Systems Architect

2022 - 2024
German Edge Cloud
  • Contributed to a solution called OpenStack On Edge. Prepared full rack deployments, starting from the HW design and the cabling. It's a turnkey solution for edge clouds, including monitoring, backup, SDN, and ZTNA VPN access.
  • Handled Ceph deployment (Rook-Ceph), Kubernetes deployment, and OpenStack deployment with the L2 network stack (BGP) configuration.
  • Developed GitOps-driven Edge OpenStack deployment pipelines. Deployed with Ansible AWX and Argo CD pipelines for cluster deployment and monitoring.
  • Resolved long-standing performance problems on the Ceph cluster by removing SSD cache parameters. Automated failed node replacements on the hyperconverged cluster.
  • Fixed hypervisor pinning and GPU-centric performance problems. CPU pinning was not possible with runC deployments. The problem was solved by finding the runC routine, and the fix was released to the runC community.
  • Utilized Ceph, Prometheus, OpenStack, Ansible, AWX, Argo CD, operators, Rancher, Cumulus OS, Supermicro servers, Cumulus switches, and IaC with Ansible AWX.
Technologies: OpenStack, Kubernetes, Ceph, GitOps, Ansible, Ansible Tower

Cloud Architect

2023 - 2023
Nekkra UG
  • Took over the system administration and migrated the services to a more stable infrastructure. Deployed Proxmox, KVM, and OpenVPN. Created a Checkmk monitoring tool with ITSM integration.
  • Defined monitoring constraints and enabled notifications.
  • Increased SLA, configured monitoring metrics, and automated scripts created for failovers.
Technologies: Node.js, Angular, HTML, PHP, JavaScript, CSS, Laravel, Vue, Redis, MongoDB, Software Engineering, Terraform

Founder

2020 - 2022
Acik Kaynak Fikirler (AKF)
  • Created opensource courses for IT, including Linux, Docker, Kubernetes, Ansible, and Scripting.
  • Built a community of around 8,000 subscribers and educated more than 10,000 people for the prepared hands-on laboratory courses.
  • Developed a course environment on Play-with-Docker and online Docker in the Docker Linux console. Keycloak and the Docker-in-Docker environment were prepared from scratch.
Technologies: Education, Training, Content Creation, VyOS, Firewalls, Infrastructure as Code (IaC), Hypervisors, Docker, MySQL, Architecture, Cloud, Continuous Deployment, Ubuntu Linux, Python, Ubuntu, Back-end, Scripting, Proxmox

Cloud Systems Architect

2017 - 2020
unbelievable Machine
  • Designed and implemented the MSP Private Cloud solution. Used Virtuozzo OpenStack and XCP-ng for the deployments.
  • Handled around 2,000 virtual instances and hundreds of hypervisors. Provided 99.998% SLA (from 96%) to our customers within six months.
  • Migrated Spectre-Meltdown of around 3,000 virtual machines from Xen to KVM. Developed a conversion script for Xen to KVM libvirt patch for hypervisors.
  • Created Kubernetes best practices on KVM hypervisors. Created oVirt and XCP-ng clusters for in-house services.
  • Handled the Virtuozzo (OnApp) hyperconverged deployment. Used Ansible IaC to manage the cloud environment.
Technologies: Ansible, KVM/Qemu, OnApp API, oVirt, Kubernetes, Xen, Citrix XenServer, VyOS, Team Management, Ansible Tower, DevOps, Firewalls, Security, Infrastructure as Code (IaC), OpenStack, Hypervisors, Docker, Elasticsearch, Amazon Web Services (AWS), Cloud Computing, Architecture, Cloud, Ubuntu Linux, Python, VPN, Networking, Ubuntu, IT Infrastructure, NGINX, Scripting

Chief Technical Officer and Co-founder

2014 - 2017
Hundertserver
  • Created a DevOps-as-a-service product and a company that provides services around that. The company had grown from 4,000 MRR in 2014 to 120,000 MRR in 2017.
  • Built the central hyper-converged system on XenServer. We used GlusterFS, DRBD, and Vyos routers on the hypervisors. I designed and implemented the systems, and my design managed more than 5,000 systems.
  • Developed a fully managed backup system for our customers. I used Bacula and Bareos backup tools and puppet automation to deploy our solution.
  • Created a ground-breaking hypervisor router environment. Each of our hypervisors had a Vyos virtual router. We scaled our infrastructure on three different continents and 10 different data centers.
  • Implemented OpenVPN mesh network and scripted and integrated Vyos.
  • Configured Mikrotik and Vyos for the customer Meinhotspot. Its 5,000 mini access points ended on our Vyos router and firewalls to reach the internet.
  • Developed the Hundertserver HS+ product. I created an automation interface in Python for our product. Puppet and Scala frameworks were used for DevOps-as-a-service environment creation.
  • Converted XenServer hypervisors to Proxmox environments. Licensing benefits on 200 servers.
  • Implemented ITSM by adopting iTOP into service management. KPI and service desk analysis began to be used as metrics for the company.
  • Introduced OKRs to the company, two cycles run before the leave.
Technologies: Puppetlabs, Ansible, Linux, Proxmox, XenServer, VyOS, MikroTik, MySQL, Elasticsearch, Checkmk, ITSM, IT Service Management (ITSM), Kubernetes, ITIL, Team Management, DevOps, Firewalls, Security, OpenStack, Hypervisors, Docker, Cloud Computing, Architecture, Training, Cloud, Ubuntu Linux, Squid Proxy Server, Proxy Servers, Squid, Python, VPN, Networking, Varnish, Ubuntu, IT Infrastructure, NGINX, Scripting

Technology Renewal and Technology Consultant

2013 - 2014
KoçSistem
  • Led a datacenter migration project for an insurance company called Allianz. We migrated the 50-racks datacenter uninterrupted, including the legacy mainframes and Oracle Exadata. A €2 million budget project was done for €250,000.
  • Acted as joint project manager for an insurance customer, BNP Paribas. Migrated their datacenter to another provider and managed Oracle, storage, and Network operations.
  • Consulted on technology renewal and governance for a pharmaceutical wholesaler company. After the consulting, the company invested €20 million less for its five-year plan. The customer was using SAP with Oracle DB and had huge performance problems.
  • Provided technology renewal and analysis consulting for a big retail company. We offered the company to use open-source alternatives on their enterprise technology stack. By consulting, they decided to use alternative databases to Oracle.
Technologies: SAP, Storage, Hypervisors, ITIL, Firewalls, Cloud Computing, Architecture, Training, Cloud, Proxy Servers, VPN, Networking, IT Infrastructure, Scripting

Chief Technical Officer

2011 - 2013
Tüm Eczac Kooperatifleri Birlii
  • Migrated legacy ERP system to SAP ERP system on a 2,000-employee organization.
  • Used open source enterprise technologies for the technology stack, including Xen, Vyatta, and Mikrotik. TCO increased by %90.
  • Managed 23 different city teams in coordination. Led technical involvement and deployment of the software in 50 branch offices.
  • Mentored and led the use of open source technologies, including Linux, Xen, KVM hypervisors, Vyatta (Vyos), Bacula backup, Openvpn, l2tp, Postfix, Samba, MySQL, Nagios, and PostgreSQL.
Technologies: SAP, IT Project Management, ITIL, IT Service Management (ITSM), Oracle, ITSM, VyOS, Firewalls, Security, Hypervisors, MySQL, Architecture, Education, Squid Proxy Server, Proxy Servers, Squid, VPN, Networking, Ubuntu, IT Infrastructure, NGINX, Scripting

Chief Information Officer

2005 - 2011
Farmalojistik A.S.
  • Implemented Oracle RAC for the company databases. Oracle 11g.
  • Managed Postfix mail server and OpenBSD packet-filter firewall implementations.
  • Wrote outbound integrations on Python and Bash scripts.
Technologies: Linux, ITSM, IT Project Management, Team Management, Oracle DBA, SAP Basis, Xen, Oracle PL/SQL, Oracle, IT Service Management (ITSM), ITIL, Amazon Web Services (AWS), VyOS, Firewalls, Hypervisors, MySQL, Architecture, Education, Squid Proxy Server, Proxy Servers, Squid, Python, VPN, Networking, Ubuntu, IT Infrastructure, Scripting, Oracle RAC

R&D Engineer

2004 - 2005
POS
  • Led development and R&D of software for gas stations.
  • Maintained software for Turkish Lira. A 6-digit reduce operation. All the statically configured values on the point-of-sale hardware were converted to use fewer digits.
  • Managed R&D using Linux on POS software. Introduced OSS to the commercial use cases.
Technologies: Python 2, C#, Delphi, MSSQLCE, Oracle, Proxy Servers, IT Infrastructure, Scripting

Kubedo Engine | A Cloud Agnostic Managed Services Platform

https://kubedo.com
A Django-based application allows clients to register Gmail and GitLab and use their Cloud credentials to deploy their infrastructure to their cloud environment.

I fully designed and implemented the software. The software triggers server-side operations via using Ansible playbooks. Monitoring is also initiating AIOPs operations by looking at the use patterns.

Hundertserver HCI Infrastructure and Creating Managed Services Company

https://hundertserver.de
I co-founded a company called Hundertserver GmbH. I was the chief architect responsible for creating our hyper-converged infrastructure.

I created a hyper-converged solution from open source tools. We used XenServer/Proxmox/KVM, GlusterFS, DRBD, VyOS, BGP, OpenVPN, Checkmk, ELK, and Ceph storage. Our solutions include managed Kubernetes and database (MySQL/PostgreSQL). I created automated cluster services on these technologies. We deployed the solutions via Puppet and Ansible. We implemented ITSM solutions around iTop.

SAP Infrastructure with Xen Hypervisors

I created the biggest architecture in the volume of billing transactions (creating 5,000 bills per hour) in the SAP R3 environment. SAP did not have a customer like that; I designed a dispatching and load balancing mechanism for SAP R3 instances. On the back end, I used Oracle Real Application Clusters (RAC), and later we migrated to Oracle Exadata.
Starting from the sizing of the environment, all the management and the R/D of the environment were created small scale. We created an IT department of 20+ people for the SAP implementation project. We managed a $60 million budget in six years.

Highlights:
I designed and implemented a very efficient and open-source infrastructure. I used Xen/Hypervisor and MikroTik routers, which saved us around %90 of the planned investments.

Languages

Python, Python 3, Python 2, C#, Delphi, HTML, PHP, JavaScript, CSS

Tools

Ansible, Ansible Tower, KVM/Qemu, Squid Proxy Server, Squid, Terraform, OpenVPN, Puppet, iTop, HashiCorp, VPN, Varnish, NGINX, Citrix XenServer, Checkmk, Keycloak, Oracle RAC

Paradigms

DevOps, Continuous Deployment, ITIL

Platforms

Linux, Kubernetes, Xen, Proxmox, XenServer, OpenStack, Docker, Ubuntu Linux, Ubuntu, Oracle, Amazon Web Services (AWS), MacOS, oVirt, Google Cloud Platform (GCP)

Storage

MySQL, Elasticsearch, DRBD, Ceph, Oracle DBA, Oracle PL/SQL, MSSQLCE, Oracle Cloud, SUSE, Redis, MongoDB

Other

Computer Engineering, VyOS, Education, Training, Hypervisors, ITSM, Team Management, Firewalls, Security, GitOps, NFS, Cloud Computing, Architecture, Cloud, Proxy Servers, IT Infrastructure, Scripting, Kubernetes Operations (kOps), MikroTik, Infrastructure as Code (IaC), High Availability Disaster Recovery (HADR), Networking, Back-end, Software Engineering, Computer Science, Content Creation, SAP, Storage, IT Project Management, IT Service Management (ITSM), SAP Basis, SAP R/3, IT Management, Failover Solutions, Oracle Data Guard

Frameworks

Django, Angular, Laravel

Libraries/APIs

OnApp API, Puppetlabs, Node.js, Vue

1996 - 2001

Bachelor's Degree in Computer Engineering

Eastern Mediterranean University - Famagusta, Cyprus

JUNE 2021 - JUNE 2024

Certified Kubernetes Administrator

Linux Foundation

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