Company with staff and sites across 5 continents. It's a both a free web hosting provider and a blockchain projects developer. Among the main functions as a system administrator:-Design, develop and manage data centers architecture: servers, storage, networks.-Configure, manage and troubleshoot servers, storage, network appliances.-Automate management and deployment of data centers resources.-Optimize existing systems for scalability and build large-scale infrastructure.-Be responsible for the high availability and proper operations of data centers.-Use a wide variety of open source technologies and tools.-Work on web-scale monitoring systems.-Work in close collaboration with developers.

System AdministratorCommercial firm with 10 branchesServers – about 10 (Windows Server 2008 R2, Windows Server 2016 Core for Hyper-V, Ubuntu, Debian, Centos)Users’ desktop – about 50 (Windows 7, 8, 10, Ubuntu Desktop, think clients)We use virtualization Hyper-V on hosts OS Windows Server 2016 Core. We use servers and technology on virtual machines - AD, Terminal Servers, MS SQL, monitoring Zabbix (on Ubuntu).File Server is used on Windows Server 2008 R2 for DFS, roaming profiles, users data.File Servers for backups are used on servers Debian 7 and CentOS 6.Net devices: managed switches -HP, D-Link, TP-Link, routers – D-link series DSR, Mikrotik.We use reservation and balancing for Internet channels, IPSec VPN site-to-site for links with branches, VPN PPTP and L2TPoverIPSec for remote users, OpenVPN for inner net. We use VLAN in managed switches.I use scripts PowerShell for automatization