Stop Feeding Claude and GPT: How to Stand Up Your Own On-Prem LLM

Shadow AI, where employees use unsanctioned AI tools, is a growing problem. An ISACA survey found that 90% of IT auditors see employees using AI, but only 38% of organizations have policies. Verizon's DBIR shows that Shadow AI is the third most common unintentional insider action, with a fourfold annual increase. Source code and images are the most leaked data. Samsung's 2023 ban on ChatGPT after several incidents illustrates the ineffectiveness of prohibition, as it only drives usage underground. Buying enterprise APIs with zero data retention also insufficient because prompts are still visible to the provider, and courts have forced OpenAI to hand over logs. The article warns that renting shared or even dedicated GPUs in the cloud is not a full solution, citing vulnerabilities like CVE-2026-46229 where VRAM can leak between tenants, and hypervisors can see everything. For most corporate needs, dedicated bare-metal hosting is sufficient, but for the highest security, own hardware is required. The article suggests starting with simpler models like Qwen3-32B for routine tasks, using Ollama for small user counts or vLLM for heavy loads, and fronting with LiteLLM as a gateway for SSO and auditing. The cost-equivalence point is at roughly 2 million tokens per day, beyond which on-premise is more economical.