Dennis Kappel
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Detailed Skills & Systems

Compact notes on systems, tools, and operational patterns I actually use.

Professional IT

Professional IT

Light side: workplace systems, administration, user-facing operations, and keeping business services stable.

Workplace Platforms

Products and environments I support in real operational contexts.

VDI / EUC
Omnissa Horizon · UAG · Connection Server · golden images · snapshotsBuilt and maintained the VDI environment together with a colleague.
Microsoft stack
Microsoft 365 administration · Exchange/mail support · Windows client/server troubleshootingDay-to-day admin and support around users, services, and incidents.
Operations
User/account support · service continuity · change coordination · backup/restore awarenessPractical business IT work where stability matters more than shiny tooling.
Documentation
Handover notes · decisions · operational context · known-good checksWriting down what changed and why so the next incident is easier.

Operational Troubleshooting

How I approach broken or unclear systems without turning the page into a command list.

Diagnosis
Logs · event messages · service states · error patterns · health checksEvidence before guessing.
Connectivity
DNS basics · routing checks · ports · HTTP status · reachability testsFollow the path from user symptom to service dependency.
Services
Process awareness · service status · failed services · restart impactLook at what is running, what failed, and what a fix might interrupt.
Users / permissions
User management · groups · ACL · file ownership · permission fixesPractical access fixes without pretending every permission issue is magic.
Validation
Before/after checks · rollout status · smoke tests · rollback awarenessSmall changes, then verify the result.
Private Infrastructure Lab

Private Infrastructure Lab

Dark side: self-hosted systems, automation, monitoring, local LLM experiments, and infrastructure learning by actually running things.

Self-hosted Systems

Infrastructure I run and maintain privately.

Hosts
Linux servers · VPS systems · Raspberry Pi · SSH · systemd · firewall basics · user managementSmall real fleet with services depending on it.
Containers
Docker · Compose · logs · inspection · health checks · configuration diffsOperate and repair services without hiding behind dashboards.
Kubernetes
k3s · Kubernetes · kubectl · Kustomize · manifests · ingress · services · rolloutsPractical cluster work from deployment to live validation.
Edge & access
Cloudflare Tunnel · NetBird · DNS · public/private routing · HTTP probesExpose only what should be public; keep administration private.
Storage
NAS · Samba · NFS · WebDAV · mounts · filesystem usage · ACL · share migrationEnough storage work to know that cutovers need patience.
Monitoring
Prometheus · Grafana · node-exporter · blackbox checks · dashboard triageObserver-style monitoring focused on finding actual problems.

Lab Automation, Local LLMs & Recovery

Tools and habits that make the lab repeatable instead of random.

Automation
Ansible roles · inventories · conservative bootstrap tasks · repeatable host setupReusable setup without destructive assumptions.
GitOps-ish
Git-backed configs · diffs · commits · deployment notes · public-edge syncNot pure GitOps theater, just traceable infrastructure changes.
Recovery
Backups · restic · rsync · restore thinking · rollback paths · migration plansAssume something will go wrong and prepare the boring escape hatch.
Local LLMs
llama.cpp · small/tuned models · local inference · command helpers · privacy-first experimentsHands-on experience with local models beyond just using hosted chat tools.
Learning
Kubernetes/CKA path · cluster observability · storage migration · networkingLearning through systems that actually have to keep working.
Honorable GitHub Projects

Honorable GitHub Projects

Small projects worth mentioning without turning the page into a portfolio wall.

nl2sh

Local-first natural-language-to-shell experiment using llama.cpp and whatisit to generate shell command suggestions from plain language. Shows practical local LLM usage, command UX thinking, and small-tool building.

local LLM · shell UX · llama.cpp
Working style

Working style

Evidence first · real tools over buzzwords · small reversible changes · keep services boring · document decisions · validate live · human-reviewed AI assistance

Evidence firstreal tools over buzzwordssmall reversible changeskeep services boringdocument decisionsvalidate livehuman-reviewed AI assistance