Dennis Johnson
About
Results-driven IT Infrastructure leader with 24+ years driving enterprise-scale transformations in healthcare. Deep expertise spanning data center architecture, cloud hybrid environments, security hardening, and team leadership. Builds and mentors high-performing infrastructure teams, fostering growth through career development and structured operational processes. Passionate about leveraging AI and large language models to automate infrastructure operations and engineering workflows.
Projects
Built a fully autonomous AI assistant running on a Mac Studio that manages infrastructure monitoring, task automation, health tracking, and daily workflows via Telegram, Discord, and web interfaces.
- đ¤ Claude AI with persistent memory and multi-session management
- đ Automated infrastructure health checks across 18+ services
- đ Intelligent calendar parsing and Workfront timesheet automation
- đ Sub-agent orchestration for parallel task execution
- đą Multi-channel: Telegram, Discord, webchat integration
- Node.js
- Claude AI
- Docker
- Cloudflare
Designed and deployed a comprehensive monitoring solution for hybrid infrastructure â tracking Windows servers, Docker containers, network devices, and cloud services with real-time dashboards and alerting.
- đ Prometheus + Grafana dashboards for full infrastructure visibility
- đĨī¸ Windows Exporter for AD, DNS, Hyper-V metrics
- đ Blackbox Exporter for endpoint availability monitoring
- đŗ Containerized deployment on Docker host
- đ Cloudflare tunnel for secure external access
- Prometheus
- Grafana
- Docker
- Linux
PowerShell-driven automation for Microsoft System Center Virtual Machine Manager â automated VM provisioning, highly available deployments, and infrastructure reporting across Hyper-V clusters.
- ⥠Automated HA VM deployment across clustered storage
- đ Infrastructure reporting with AD, DNS, and compute metrics
- đ§ PowerShell modules for SCVMM management
- đĨī¸ Remote management via SSH relay from Mac/Linux
- PowerShell
- Windows Server
- Hyper-V
End-to-end health data platform integrating Apple Health data with AI-powered macro estimation, workout tracking, and clinical health monitoring via a dedicated AI assistant.
- đ Apple Health auto-sync via REST API
- đĨ AI-powered macro estimation using local LLMs (Ollama)
- đĒ Workout logging and exercise tracking
- đ¤ Dedicated Haiku-powered health bot on Telegram
- Node.js
- Docker
- Ollama
- Claude AI
Raspberry Pi-powered robot car with AI vision capabilities â Claude-powered brain for autonomous navigation, obstacle detection, and voice interaction via custom relay server.
- đĨ Camera with pan-tilt mount for vision analysis
- đ§ Claude Vision API for scene understanding
- đ Text-to-speech via I2S DAC audio system
- đšī¸ Natural language command interface
- Python
- Raspberry Pi
- Claude AI
- Node.js
Enterprise-wide virtualization platform migration from VMware vSphere to Microsoft Hyper-V â consolidated 800 VMs to 350 while optimizing resource utilization.
- đ Migrated entire VMware estate to Hyper-V/SCVMM
- đ Consolidated 800 VMs to 350 (56% reduction)
- ⥠Optimized resource utilization across clusters
- đĄī¸ Zero unplanned downtime during migration
- VMware
- Hyper-V
- PowerShell
- SCVMM
Migrated enterprise network security from VMware NSX to Illumio for host-based micro-segmentation, enhancing zero-trust posture across the entire infrastructure.
- đ VMware NSX â Illumio migration
- đĄī¸ Host-based micro-segmentation across all workloads
- đ Real-time application dependency mapping
- â Enhanced zero-trust security posture
- Illumio
- NSX-T
- PowerShell
Designed and implemented VMware NSX-T Federation between multiple data centers for unified network virtualization and consistent security policy enforcement.
- đ NSX-T Federation across multiple data centers
- đ Unified network policy management
- đĄī¸ Consistent micro-segmentation across sites
- đĄ Stretched networking for workload mobility
- NSX-T
- vCenter
- Cisco
Built automated security patching and vulnerability remediation across the entire Windows Server fleet using Ansible and Puppet, replacing manual processes.
- đ¤ Automated OS patching across Windows Server fleet
- đ§ Ansible playbooks for configuration management
- đĄī¸ Automated vulnerability remediation across all devices
- đ Compliance reporting and audit trail
- Ansible
- PowerShell
- Windows Server
Migrated enterprise backup and disaster recovery from legacy IBM Tivoli Storage Manager to Rubrik, modernizing data protection with instant recovery and cloud-native capabilities.
- đž IBM TSM â Rubrik migration
- ⥠Instant VM recovery capability
- âī¸ Cloud-native backup and archival
- đ Reduced RTO from hours to minutes
- Rubrik
- VMware
- Azure
Complete physical-to-virtual migration of an entire data center environment â designed ESX clusters with HA, DRS, and distributed switches on Cisco UCS and EMC storage.
- đ 100% physical to virtual conversion
- đī¸ ESX Clusters with HA, DRS, Distributed Switches
- đĨī¸ Cisco UCS compute + EMC VNX storage platform
- đ Improved resource utilization and disaster recovery
- VMware
- Cisco UCS
- EMC
Multi-phase enterprise storage migration from IBM legacy platforms to all-flash Pure Storage, dramatically improving IOPS performance and reducing management overhead.
- đž IBM XIV â IBM V7000 â Pure Storage migration path
- ⥠All-flash arrays â massive IOPS improvement
- đ Reduced storage management overhead
- đ Non-disruptive data migrations
- Pure Storage
- VMware
- PowerShell
Designed secure remote site access over 3G networks for military training simulators deployed in isolated field locations â enabling real-time data sync and management from HQ.
- đī¸ Remote access for military trainers in isolated locations
- đĄ Secure connectivity over 3G cellular networks
- đ VPN tunnels with encryption for classified environments
- đ Real-time data sync between field and HQ
- Cisco
- Windows Server