Infrastructure

TL;DR I bought nine Dell OptiPlex all-in-ones (a mix of 7760 and 7780) in one government surplus lot for $1,209.37 all-in, about $134 a unit. Tax and shipping were zero; I picked them up myself. They run Debian 13 with a LUKS-encrypted root that unlocks through the TPM, Secure Boot on, and a signed NVIDIA module. Getting all three to coexist was most of the work. Eight of them joined my second, small k3s cluster (the “office cluster” at the shop where I do resale and bench work) as workers. Together they add 96 cores and 170 GiB of allocatable memory to a cluster whose three agent VMs had 12 cores and 23 GiB between them. The join is a dedicated Ansible playbook that reuses the existing k3s_agent role. One canary first, then the other seven in two waves. I didn’t measure power draw on these, so there’s no watts figure in this post. The older OptiPlex desktop cluster number doesn’t transfer. Why all-in-ones Most of what I buy for the hobby that funds the hobby is resale stock. This lot was different: nine machines, all wiped, “last powered on six months ago”, sold as-is, pickup by appointment at a school. The seller doesn’t box or ship. The hammer price was $1,075.00, plus a $134.37 buyer premium. I allocated the cost per unit in the inventory database and marked all nine as kept rather than for sale. ...

TL;DR My production homelab runs on Lenovo M920q tinies, and I still think those are the sweet spot. But if I were starting over today with a tight budget, I’d buy a stack of government-surplus Dell OptiPlex 7060 and 7070 desktops instead. They go for around $150 each refurbished — 6-core 8th/9th-gen Intel, an SSD, and Windows 11 already on them — and they make excellent Kubernetes nodes with exactly two cheap upgrades: a bit more RAM and a second network card. ...

TL;DR The homelab runs 42 Kubernetes namespaces across 7 nodes (3 control plane, 4 workers) on 4 Lenovo ThinkCentre M920q mini PCs running Proxmox VE. This post is the result of a full infrastructure audit — reconciling what’s actually running against what’s documented, catching version drift, and noting what’s been added, removed, or broken since the last check. Compute Four Lenovo ThinkCentre M920q nodes form the physical layer: Host CPU RAM NVMe Role pve1 i5-8500T 32GB 512GB 1 server VM + 1 agent VM pve2 i5-8500T 32GB 512GB 1 server VM + 1 agent VM pve3 i5-8500T 32GB 512GB 1 server VM + 1 agent VM pve4 i7-8700T 32GB 512GB 1 agent VM (GPU passthrough) The k3s cluster runs v1.34.4+k3s1 with embedded etcd for HA. All 7 nodes report Ready. Server VMs get 2 cores and 6GB each — just enough for etcd and the API server. Agent VMs are beefier: 6 cores and 22GB on pve1-3, 12 cores and 28GB on pve4. ...

TL;DR I spent time evaluating Linkerd — the CNCF graduated service mesh — for my homelab k3s cluster. The conclusion: it’s an impressive piece of engineering with genuinely useful features like automatic mTLS, post-quantum cryptography, and per-service observability. But for a cluster with ~20 workloads and a single operator, the operational overhead outweighs the benefits today. I’ve written a complete deployment plan so I can adopt it quickly when the cluster grows to the point where it makes sense. ...