Open to Opportunities

Darwin Marmolejos

IT professional focused on cloud infrastructure & cybersecurity. CompTIA Network+ certified, building hands-on Linux and security skills daily.

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About

About Me

I break things in my home lab on weekends and write scripts to fix what I broke. I interned at Mimecast managing enterprise tooling across a global environment, and I'm about to start as an IT Helpdesk Support Specialist at 1A Auto. I've built 21+ bash scripts for everything from server hardening to DDoS mitigation, and I'm most energized when I'm deep in a terminal solving a problem nobody's documented yet.

Certifications & Roadmap
CompTIA Network+
✓ Earned December 2025
AWS Cloud Practitioner
● In Progress
Network+
→
AWS CCP
→
Security+
→
AWS Solutions Architect
Work Samples

Selected Work

⚙ Home Server — Windows Server 2019

Configured a virtualized Windows Server 2019 environment with Active Directory, VLAN segmentation, firewall rules, and ACLs. Simulated AD authentication workflows and conducted privilege escalation testing to identify misconfigurations. Documented network topology, firewall rule logic, and lessons learned from the escalation exercise.

Windows Server Active Directory VLANs Firewall / ACLs Privilege Escalation

▶ Linux Admin Scripts Collection

A repository of 21 shell scripts covering server hardening, firewall automation, health monitoring, network diagnostics, DDoS prevention, and emergency recovery — built throughout CIS-245. Each script solves a specific sysadmin problem with production-style error handling and logging.

Bash Security Automation 43 commits
View on GitHub →

⚡ Smart Grids & AI in Renewable Energy

Research paper exploring how AI-driven monitoring and predictive analytics apply to critical infrastructure — relevant to how similar techniques are used in SIEM platforms and infrastructure security for anomaly detection and automated response.

Research Paper AI / ML Infrastructure Monitoring
Scripts

Shell Scripts

21 scripts built for Linux administration coursework and personal projects. Full repo →

🔒 Server Hardening & Rollback

server_hardening.sh 723-line Ubuntu hardening (SSH, firewall, audit logging, services) rollback_hardening.sh Rollback for Ubuntu hardening changes centos_hardening.sh CentOS-specific server hardening centos_rollback.sh CentOS hardening rollback alt_hardening.sh Alternative hardening approach alt_rollback.sh Matching rollback script

🔥 Firewall & Network Security

task1_webserver.sh Web server firewall rules task2_mysql.sh MySQL port access control task3_ssh_allow.sh SSH allow rules task3_ssh_deny.sh SSH deny rules task4_block_hosts.sh Host-based blocking task5_block_ping.sh ICMP ping blocking task5_block_telnet.sh Telnet service blocking ddos_prevention.sh Rate limiting & DDoS mitigation rules

📈 Diagnostics & Monitoring

ServerHealthCheck.sh Full server health report (disk, memory, services) server_diag.sh System diagnostics summary network_dump_darwin.sh Network config & routing dump troubleshooter.sh Interactive troubleshooting tool

🔄 Recovery & Setup

emergency_reset.sh Ubuntu emergency system reset emergency_reset_centos.sh CentOS emergency system reset centosprep.sh CentOS environment setup & prep reboot.sh Controlled reboot with pre-checks
Resume

Resume

A.S. in Computer Science — Networking & Security Assurance

Northern Essex Community College · May 2026

Relevant Coursework: Linux Administration, Database Management, Computer Networks III, Programming for IT (C), Python, Bash / Shell Scripting.

Certifications

CompTIA Network+ — Earned December 2025
AWS Cloud Practitioner — In Progress

Skills

MDM Solutions Active Directory Identity Management Ticketing Systems Remote Support Tools Linux (Ubuntu / CentOS / Kali) Windows Server Bash / Shell Scripting SQL Python AWS (EC2, S3, RDS) Networking (TCP/IP, DNS, DHCP) iptables / Firewall Config

IT Helpdesk Support Specialist

1A Auto · MA · May 2026 – Present

Information Technology Intern

Mimecast · MA · July 2025 – March 2026
  • Resolved an average of 100+ technical support cases monthly through the company ticketing system, delivering end-user support across a global enterprise environment.
  • Supported secure onboarding and offboarding workflows, including user provisioning, deprovisioning, and access management through ACLs and distribution lists.
  • Managed and troubleshot endpoint devices using MDM platforms, performing remote remediation and support.
  • Contributed to internal Knowledge Base documentation to improve operational efficiency, standardization, and security awareness across IT processes.
  • Maintained global IT asset inventory through weekly audits, ensuring accurate tracking and lifecycle management of hardware and software resources.

Home Server — Computer Networks III

Academic Project
  • Configured a Windows Server 2019 virtualized environment with Active Directory, VLAN segmentation, and group policy enforcement.
  • Implemented firewall rules and ACLs to restrict unauthorized inter-VLAN traffic and conducted privilege escalation testing to validate security controls.