Georgios Sarris Tzamtzis Email & Phone Number

Athens, Attiki, Greece

Athens, Attiki, Greece

Athens, Attiki, Greece

Athens, Attiki, Greece

Manchester, United Kingdom

Manchester, United Kingdom

Manchester, United Kingdom

London, United Kingdom

London, United Kingdom

Product Madness is a hot social and mobile gaming company. With offices in London and San Francisco, Product Madness is a leader in the industry and now a part of the Aristocrat family - the second largest manufacturer of slot games in the world.I am a member of DevOps team. The most significant project we are working on is the move from Shared Hosting to Co-location. We are planning and preparing together with my Manager this move, planning to complete this in 2015. Apart from this Project, my day-to-day tasks include working a lot with Chef. Apart from Chef, day-to-day tasks include working with Databases (backup automations, maintenance) as well as participate to side projects (like a JIRA migration).

London, United Kingdom

Opta (also known as OptaSports) is the world's leading Sports Data company and is owned by digital sports media group PERFORM. Opta main service includes collecting, packaging, analysing and distributing live data. As a Systems Administrator, the tasks I undertake include (but are not limited to):- Build, configure and maintain the Servers (both Physical and VMs) running Debian Linux -as well as few Servers running Windows (Domain Controllers, Exchange) and few running CentOS (mostly legacy hosts) - Built with my colleagues the new Datacenter (server racking, cabling, network configuration, built the Virtualised Environment, built new Database Clusters) - Manage, Maintain and update the MySQL DB Servers (running MySQL Percona Server with Galera as well as stock MySQL)- Monitoring the Infrastructure using the monitoring tools we have installed and configured (Zabbix, Nagios, NewRelic, Smokeping) making sure that everything is fine and there are no alertsManage the Puppet Infrastructure- Together with my team, we maintain and expand when needed the Corporate Network (both design and configure including Cisco Switches and Routers) - Participate in meetings regarding existing and new services, actively contributing in order to ensure that the right decision is taken regarding the way things should be done - Completed the upgrade from MySQL 4.1 to Percona MySQL Cluster with Galera features enabled successfully- Use our ticketing system (RT) to manage tickets raised for our team- Managed all the Domain Names that belong to the company- Creating various documentation when needed in our internal Wiki serviceAlso, I participate in my team’s on-call rota, supporting the Infrastructure on non-working hours.

London, United Kingdom

Betfair is among the biggest gambling Companies all over the World with innovative products including Bet Exchange, Sportsbook and various online games. Working on an agile environment, I am member of the I&P (Infrastructure and Platform) team. My team is responsible for all the Linux Servers that are used for the main IT Infrastructure as well as for the production servers. We are supporting - maintaining the OS at around 5000 to 6000 servers that are used in different environments (development, pre-production, production, PCI). My main responsibilities -as a member of the team- include (but not limited to) :Building Servers (VMs, Physical Boxes) using Cobbler, Kickstart and Puppet to automate the processAutomate tasks around the Infrastructure using Puppet and HieraMaintain, Patch and Upgrade the OS on Linux (Red Hat and CentOS mostly) Servers Install, Configure, Support and Maintain Services including LDAP (389-DS), Spacewalk, Splunk, Opsview, BindWork closely with other teams (Network, Storage, DBA) to address issues as well as to plan future updates and changesBuild, Configure and Maintain the entire Virtualization Infrastructure based on Xen (includes building HVs, supporting in-house built tools to automate VM building using Xen API and more written in Python)Maintaining and supporting VCS ClustersContacting Suppliers -like Red Hat, Citrix and more- to address issues we hadPatching and keeping up-to-date the entire PCI Zone, in order to preserve the PCI Compliance and secure the hosts and the data in the PCI ZoneCreating various documentations like troubleshooting guides, manual for custom tools, as well as contribute guides to our internal knowledge wikiAlso, I was participating in my team’s on-call rota, supporting the Infrastructure on non-working hours.

Kingston Upon Thames, United Kingdom

Freezone is among the Top-10 Webhosting Providers in UK. Freezone has around 35 Hosts (Virtual Machines included) running RedHat, CentOS, Debian and FreeBSD. I was member of the IT Department as Senior Linux Administrator. My key responsibilities were:Deploying new servers -using Kickstart, Cobbler and Puppet for Automation- (Virtual Machines on XEN and Physical Servers)Maintaining, Patching and Upgrading Servers running Linux/Unix OSMonitoring and Configuring SAN Daily Monitoring (Nagios, Cacti) Troubleshooting all kind of issues (OS related, Application - Service related, Hardware related, Network related)Frequent visits to our Datacenter to ensure that everything was working properlyResponsible for all Network and Server Security planning Monitoring, configuring and supporting MySQL ServersMonitoring Backup Tasks, ensuring everything was completed successfullyAlso, I was responsible for network performance, servers security and stability. Any change that has to be made is my task to decide about it and ensure that it will work as we want.

I was member of the IT Department as Corporate IT Infrastructure and Hosting Services Engineer. Corporate Network has around 20 Windows Servers and around 50 Linux / Unix Servers and also, there are around 350 workstations. As a member of this Department and member of Administrator’s Group, I was System Administrator on Servers that serve the Corporate Network in Linux/Unix OS. More specifically:- DNS Servers running Bind on Solaris- Email Servers running Postfix on CentOS- NFS Servers running on CentOS- Apache Webservers running on CentOS- Asterisk VoIP Servers running on Red HatAdditionally, I managed (Installation, Configuration, Support, Administration) of the Network Equipment that belongs to the Corporate Network (Dell Switches, Cisco Switches). I was also the System Administrator on the Servers that are hosting Plesk Parallel Panels (running on Red Hat Linux) and are used to offer Web Hosting Services to Company's customers. My role was installing, upgrading and supporting these Servers and additionally, solve issues of the offering Services (Email Service -Qmail-, DNS Service -Bind-, Apache Webserver, PHP, MySQL Database).Also, as a System Administrator and member of the IT Department, I was taking part on analysing, designing and applying all the required security measures in order to ensure Systems and Network Security, maximize Services Availability and ensure Data Integrity.I also worked closely and assisted the Windows Administration Team and I got some hand-on experience on Administrating MS Windows Server OS (2003 and 2008 R2) and MS Windows Based Services (Active Directory, MS Exchange Server, Sharepoint, WDS, IIS, MS Communicator).

Since 2003 I was student member in the Network Operation Centre (ATEI / Lamia). More specific, I was member of Network Department and after 6 (six) months, I took a promotion be chief of that Department. The issues I deal with success were: Design, Analysis, Development and Network Extension Monitoring for potential failures Maintenance of equipment and cable infrastructure Performance Monitoring - SNMP Security Design and Development of Wireless Network Administrator of Cisco Network Devices (Installation - Configuration)

Bachelor Of Science (Bsc), Computer Science

Education record