Skip to content
View kelvinmarcar's full-sized avatar
  • ICT Technician – Data Center Operations
  • Sweden
  • 14:41 (UTC -12:00)
  • LinkedIn in/kelvin-marcar

Block or report kelvinmarcar

Block user

Prevent this user from interacting with your repositories and sending you notifications. Learn more about blocking users.

You must be logged in to block users.

Maximum 250 characters. Please don’t include any personal information such as legal names or email addresses. Markdown is supported. This note will only be visible to you.
Report abuse

Contact GitHub support about this user’s behavior. Learn more about reporting abuse.

Report abuse
kelvinmarcar/README.md

Kelvin Jacob Marcar

ICT Technician | CompTIA Security+ | Microsoft 365 & Active Directory Labs | Identity, Device Management & Enterprise IT Administration


About Me

I work in data center operations and continuously build hands-on labs to strengthen my skills in enterprise IT administration.

My focus is on Microsoft environments including Active Directory, Microsoft 365, identity management, device management, and enterprise infrastructure. I use home labs to simulate real-world administrative scenarios involving user management, security policies, device enrollment, troubleshooting, and collaboration services.

My goal is to continue developing practical experience in enterprise IT environments while progressing toward system administration and cloud administration roles.


Core Skills

• Active Directory administration
• Microsoft 365 administration
• Microsoft Entra ID identity management
• Windows Server configuration
• User and group lifecycle management
• Microsoft Intune device management
• DNS configuration and troubleshooting
• Endpoint device administration
• Network fundamentals and troubleshooting
• Enterprise infrastructure lab design


Featured Projects

Active Directory Home Lab

A small enterprise-style Windows Server environment built using Windows Server 2025 and a Windows 11 client workstation to simulate common IT administration tasks.

Key implementations:

• Domain Controller deployment
• DNS configuration
• Organizational Unit (OU) structure
• Security groups and role-based access control (RBAC)
• User lifecycle management (create, reset password, disable accounts)
• Domain-joined Windows 11 client workstation
• Role-based shared folder permissions

Project documentation and screenshots:
https://github.com/kelvinmarcar/active-directory-home-lab


Microsoft 365 Enterprise Administration Lab

Hands-on Microsoft 365 enterprise administration lab covering identity management, security configuration, device management, and collaboration services.

Key implementations:

• Microsoft Entra ID user and group management
• Multi-Factor Authentication (MFA) configuration
• Conditional Access security policies
• Microsoft Intune device enrollment and compliance
• Windows 11 device management
• Exchange Online shared mailbox configuration
• Microsoft Teams collaboration channels
• Microsoft Defender monitoring
• Entra ID sign-in log auditing

Project documentation and screenshots:
https://github.com/kelvinmarcar/microsoft-365-enterprise-admin-lab


IT Support Troubleshooting Lab

Hands-on IT support lab demonstrating structured troubleshooting across Windows and Linux systems in a simulated enterprise environment.

Key implementations:

• Windows performance diagnostics using Task Manager and Event Viewer
• DNS troubleshooting across Windows and Linux systems
• Investigation and resolution of IPv6 DNS precedence issues
• DHCP service verification on Windows Server
• Remote server support using SSH on Ubuntu Server
• Network diagnostics using ping, ipconfig, nslookup, and dig
• System security verification and infrastructure validation

Project documentation and screenshots:
https://github.com/kelvinmarcar/enterprise-it-troubleshooting-lab


Enterprise Network Troubleshooting Lab

Enterprise network troubleshooting lab demonstrating structured OSI-layer diagnostics across Windows, Linux, and network infrastructure.

Key implementations:

• DNS failure investigation and hostname resolution troubleshooting
• Network diagnostics using ping, nslookup, ipconfig, and routing analysis
• Firewall verification and infrastructure validation using pfSense
• Linux network diagnostics and system-level troubleshooting
• DNS forwarder configuration and enterprise DNS troubleshooting
• Root cause analysis and corrective network configuration
• Final infrastructure verification and connectivity validation

Project documentation and screenshots:
https://github.com/kelvinmarcar/enterprise-network-troubleshooting-lab


Certifications

• CompTIA Security+
• CompTIA Network+
• CompTIA A+
• ISC2 Certified in Cybersecurity (CC)
• Microsoft Azure Fundamentals (AZ-900)
• Microsoft 365 Fundamentals (MS-900)
• Google IT Support Professional Certificate


Career Focus

I am currently focused on building practical experience in:

• IT Support and Infrastructure Administration
• Windows Server and Active Directory environments
• Microsoft 365 administration
• Identity and access management
• Device management and endpoint administration
• Enterprise troubleshooting and system diagnostics

Target roles include:

• IT Support Technician
• IT Technician
• Junior System Administrator
• Junior Cloud Administrator
• Microsoft 365 Administrator (Entry Level) image

Pinned Loading

  1. active-directory-home-lab active-directory-home-lab Public

    Active Directory home lab demonstrating domain deployment, user lifecycle management, group-based access control, and enterprise-style IT administration using Windows Server 2025.

  2. microsoft-365-enterprise-admin-lab microsoft-365-enterprise-admin-lab Public

    Hands-on Microsoft 365 Enterprise Administration lab covering Entra ID, MFA, Conditional Access, Intune device management, Exchange Online, Teams collaboration, and Microsoft Defender monitoring.

  3. enterprise-it-troubleshooting-lab enterprise-it-troubleshooting-lab Public

    Enterprise IT Troubleshooting Lab demonstrating Windows and Linux troubleshooting, DNS diagnostics, DHCP verification, SSH remote support, and system security validation.

  4. enterprise-network-troubleshooting-lab enterprise-network-troubleshooting-lab Public

    Enterprise network troubleshooting lab demonstrating OSI-layer diagnostics, DNS troubleshooting, firewall verification, and root cause analysis in a simulated enterprise infrastructure.