Nikos Tzelvenzis, Developer in Thessaloniki, Greece
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Nikos Tzelvenzis

Verified Expert  in Engineering

DevOps Engineer and Developer

Location
Thessaloniki, Greece
Toptal Member Since
July 15, 2020

Nikos是一名DevOps工程师和基础设施设计师，拥有多年的实践经验, 这包括建立一个拥有至少700万用户的高流量平台. 在那个项目中，整个基础设施是根据负载和交通水平扩展的. 由于日志的大小，这里的挑战与流量的大小有关——特别是审计和日志记录, etc. were much larger than usual. 可以肯定地说，无论您的DevOps需要什么，Nikos都可以处理它们.

OpenStackDevOpsAmazon S3 (AWS S3)Amazon EBSAWS HAAmazon EC2AWS CLITerraformSystem AdministrationBashOpenVPNAnsiblePythonAmazon ElastiCacheKubernetes

Portfolio

Schoox Inc
Amazon Web Services (AWS)， PHP, Kubernetes, Python, Amazon EBS...
Datajolt Limited
Python, Amazon Web Services (AWS)， DevOps, Flask, Kubernetes, Scaling, AWS ALB...
NebulOS, Inc.
Linux, Ubuntu, OpenStack, Data Centers, Ceph, Bash

Experience

OpenStack - 4 yearsAnsible - 4 yearsAzure - 3 yearsJenkins - 2 yearsAmazon EC2 - 2 yearsTerraform - 2 yearsKubernetes - 2 yearsHelm - 1 year

Availability

Part-time

Preferred Environment

Firefox, Visual Studio Code (VS Code), Bash, Linux

The most amazing...

...项目正在开发一种可扩展的方法，在S3存储中意外删除了2000万个文件后，可以在2小时内恢复所有文件而不会中断服务.

Work Experience

Director of DevOps

2018 - PRESENT
Schoox Inc
  • 在云基础设施中创建了一个新的安全网络，并帮助公司存档安全认证，以接受新的和更重要的客户.
  • 设计并启用监控审核平台，帮助支持部门更自信地回答客户的问题.
  • Transformed the build and deploy procedure. Previously, the company used git pull as the deployment method, which caused HTTP errors; now, 节点的升级没有流量，也没有HTTP错误.
Technologies: Amazon Web Services (AWS)， PHP, Kubernetes, Python, Amazon EBS, Amazon Route 53, Amazon EC2, Bash, Ansible, Amazon ElastiCache, Docker, Jenkins, Amazon CloudFront CDN, Continuous Delivery (CD), MongoDB, AWS CloudFormation, Linux, Firefox, SAML, AWS ELB, AWS CLI, Terraform, OpenVPN, Amazon EKS, Amazon Simple Queue Service (SQS), Continuous Integration (CI), Helm, Cloud, System Administration

DevOps Engineer

2023 - 2023
Datajolt Limited
  • 解决了在使用AWS应用程序负载均衡器作为入口资源的EKS部署中的网络问题.
  • 建议为分布和部署在EKS集群中的应用程序保留日志的更好方法. 听取公司需求，根据预算提出2 - 3个解决方案.
  • 检查了基础设施的现有安全状态，并根据他们给我访问AWS账户的方式评估了数据访问.
Technologies: Python, Amazon Web Services (AWS)， DevOps, Flask, Kubernetes, Scaling, AWS ALB, Gunicorn, Terraform, Bash, Docker, AWS ELB, AWS CLI, Helm, Cloud

Senior DevOps Engineer

2021 - 2022
NebulOS, Inc.
  • Solved problems in a Ceph cluster with node outages. 集群不稳定，所有写操作都被禁用，因此需要重新平衡集群.
  • 在现有集群中新增4个节点，并更新OpenStack版本. 设置新的虚拟网络，并开始使用该集群上的新客户机. 为windows创建并发放新的OpenStack镜像.
  • 在美国下班时间，与其他技术成员一起支持现有的Oracle VM集群.
技术:Linux, Ubuntu, OpenStack，数据中心，Ceph, Bash

DevOps Engineer

2021 - 2021
Piggy, LLC
  • Changed, working as a developer focused on security, 应用程序对AWS的访问从静态密钥到IAM角色.
  • 设计并编写Lambda函数，自动旋转RDS数据库的凭据.
  • 审查并修复了安全组和对基础设施的访问.
Technologies: Amazon Web Services (AWS), Terraform, CI/CD Pipelines, Automation, Amazon RDS, Bash, Kubernetes, Linux, AWS CLI, Continuous Integration (CI), Cloud

DevOps AWS Engineer

2021 - 2021
ZYP.ONE GmbH
  • Designed and created the entire environment (production, staging, 使用Terraform和OpenVPN创建网络来访问环境，而无需启用公共访问.
  • Migrated the database to RDS, configured database backups, and unique dump exports to S3 with an ECS service.
  • 安装并配置带有主节点和动态从节点的Jenkins CI/CD系统.
  • 改进了自动化管道，以便更好地与CI一起工作，并为测试和登台环境准备了CD部分.
Technologies: Amazon Web Services (AWS), Terraform, Docker, VPN, Networks, Jenkins, GitHub, AWS Batch, Bash, Linux, AWS CLI, Continuous Integration (CI), Cloud

软件开发人员| Oracle数据库专家|基础架构师

2005 - 2018
Logismos SA
  • 部署OpenStack作为公司私有云解决方案.
  • 使用Ceph将存储转换为更集中的存储，并且可以在不中断服务的情况下进行维护.
  • 在全球不同国家的多个站点之间设计并实现了近实时的两个系统之间的集成服务.
  • 安装和配置一个Oracle数据库，并为两个不同的主机提供备用服务和自动备份，不中断.
Technologies: Ceph, Oracle, OpenStack, Bash, Ansible, Python, Linux, Java, SAML, OpenVPN, System Administration

恢复Amazon S3桶中2000万删除文件

事故发生后，一个进程开始快速删除两个桶中的文件. 桶启用了版本控制，但我们需要启动一个流来恢复数据. To solve this, 我用队列和Lambdas创建了一种机制，它可以找到文件并恢复它们(I.e., deleting the deletion mark).

Worker Daemon in Python

一个Python应用程序，作为Linux守护进程使用来自Amazon SQS队列的消息，并在PHP环境中执行它们. 该守护进程使用度量发布到Amazon CloudWatch度量服务和Amazon S3中的敏锐审计日志.

Scalable Logging Parser

With the ELK stack, 我使用了一种带有队列的可伸缩方式来解析Amazon S3 Storage中的文件，并在Elasticsearch集群中填充数据以进行审计. 解析发生在Kubernetes集群中，并使用S3事件和队列来实现异步解析.

SSO Authentication with All Internal Services

由于员工数量的增加，一家初创公司决定启用Okta的用户存储库. I designed and implemented the authentication, authorization, and internal portals with Okta (SAML and OpenID). The internal services include the AWS console, CLI, 以及所有Dockerized/Kubernetes应用程序，如调度程序和日志工具，如Elasticsearch.

SOC2 Certification

我是通过SOC2审核并获得公司资格的团队成员.
该团队涉及报告和程序，以保持任何安全方面，并跟踪到审计跟踪. 最后，我们应用审核组请求的任何更改.

Frameworks

AWS HA, Flask

Tools

Amazon EBS, AWS ELB, AWS CLI, Terraform, Amazon ElastiCache, Ansible, Helm, Amazon EKS, OpenVPN, Amazon Simple Queue Service (SQS), Jenkins, Amazon CloudFront CDN, AWS Batch, AWS CloudFormation, VPN, GitHub, Amazon CloudWatch, ELK (Elastic Stack)

Paradigms

DevOps，持续交付(CD)，持续集成(CI)， DevSecOps，自动化

Platforms

Amazon EC2, OpenStack, Kubernetes, Docker, Amazon Web Services (AWS), Azure, Linux, Firefox, Oracle, Visual Studio Code (VS Code), AWS ALB, Ubuntu, AWS Lambda

Storage

Amazon S3 (AWS S3), Ceph, MongoDB, Data Centers

Languages

Python, Bash, PHP, Java, SAML

Other

Amazon Route 53, System Administration, Electronics, Microcontrollers, Circuit Design, Okta, Single Sign-on (SSO), Security, Cloud, Networks, CI/CD Pipelines, Amazon RDS, Scaling, Gunicorn

Libraries/APIs

OpenID

1998 - 2004

Bachelor's Degree in Electronics

Technical University - Thessaloniki, Greece

SEPTEMBER 2019 - SEPTEMBER 2022

AWS Certified SysOps Administrator — Associate

AWS