Guillermo Becerra

Senior IT Infrastructure & Server Administrator with 12+ years of experience managing enterprise Windows and Linux environments, specializing in server administration, VMware virtualization and AWS infrastructure. Strong expertise in Active Directory, networking, monitoring and infrastructure security, with hands-on experience using Nagios, Zabbix, Grafana and Prometheus to monitor service health, alerts and performance metrics. Experienced in infrastructure troubleshooting, migrations and automation using PowerShell, Bash and Python, focused on maintaining availability, stability and operational continuity.

Server Administrator at STARTEK ARGENTINA (2014 – Present)

• Administer enterprise Windows and Linux server infrastructure, ensuring availability, stability, security and operational continuity.
• Manage Windows Server environments including Active Directory, Domain Controllers, DNS, DHCP, Group Policy, WDS, IIS, RDS/RDP, WSUS and File Servers.
• Administer Linux servers including Ubuntu, Debian, CentOS and Red Hat.
• Manage VMware ESXi/vCenter and Microsoft Hyper-V environments, including virtual machines, snapshots, resource allocation and infrastructure maintenance.
• Administer Microsoft Exchange environments and participate in mail platform migrations.
• Implement and maintain infrastructure monitoring using Nagios, Zabbix, Grafana, monitoring service health, alerts and performance metrics.
• Analyze CPU, RAM, disk I/O, service availability and network performance to identify degradation, failures and potential availability issues.
• Investigate infrastructure alerts and events, troubleshoot service failures and implement corrective actions to maintain system availability.
• Manage backup environments using Veritas and Windows Server Backup, including backup verification and recovery procedures.
• Troubleshoot incidents involving servers, operating systems, applications, networking and virtualization.
• Configure and troubleshoot TCP/IP, DNS, DHCP, VPN and firewall-related issues.
• Perform server hardening, patch management, vulnerability remediation, EDR administration, security configuration and log analysis.
• Administer Dell and HP server hardware, including iDRAC and iLO management and hardware troubleshooting.
• Implement and maintain Group Policy environments and automate administrative tasks.
• Develop administration and support scripts using PowerShell, Bash, Batch, VBScript and Python.
• Develop self-service tools for Windows, Office, printers, email, passwords, Active Directory, networking and workstation support.
• Participate in infrastructure migrations, including domain migrations, server migrations and VMware-to-AWS workloads.
• Hands-on AWS administration with EC2, VPC, subnets, Internet Gateway, NAT Gateway, snapshots and AWS CLI.
• Support Windows/Linux workloads in AWS, including Active Directory, File Servers and SQL environments.
• Collaborate with infrastructure and support teams to diagnose incidents and implement stable technical solutions.

Help Desk / Technical Support at Aegis Argentina (2008 – 2014)

• Provided technical support to corporate users for hardware, software, Windows operating systems, networking, printers and business applications.
• Responded to and resolved technical support requests and incidents from end users, ensuring timely restoration of service.
• Troubleshot Active Directory accounts, passwords, email, connectivity and network-related incidents.
• Supported users through incident resolution and provided technical guidance according to corporate procedures.
• Trained and assisted new employees in the use of internal systems, applications and IT resources.
• Performed workstation deployment, operating-system installation, configuration and maintenance.
• Supported remote users and escalated complex infrastructure incidents to specialized teams.
• Created, updated and maintained support tickets, documenting incidents, troubleshooting steps, solutions and technical actions performed.
• Worked to restore service quickly while maintaining user productivity and business continuity.

IT Support & Network Administration at INDEPENDENT IT SERVICES (2004 – 2007)

• Managed day-to-day technical operations of a cybercafé environment, providing hardware and software technical support to users.
• Installed, configured and maintained Windows workstations and local network infrastructure.
• Managed the configuration and maintenance of LAN connectivity, Internet access, printers and shared network resources.
• Troubleshot hardware, software, operating-system, connectivity and system performance issues.
• Performed PC maintenance, operating-system installations, hardware upgrades and preventive maintenance.

Architecture Studies — Up to 3rd Year in Architecture

PC Repair & Maintenance — Technical Training in PC Repair & Maintenance