# AGENTS.md — Proxmox Performance Optimization Project

**Read this first.** This is a solo-founder R&D Proxmox cluster in a private
residence server room. Shoestring budget. Redundancy is NOT a concern — this
is for batch jobs. Backups DO matter (PBS in use). Production lives elsewhere.

**Three .md files exist:**
- `AGENTS.md` (this file) -- operating context for the AI agent
- `PROJECT.md` -- comprehensive board-ready report for the user
- `K8S.md` -- kubernetes architecture deep-dive (for a future session)

## Current state (as of 2026-07-27)

### DONE — 5 of 7 hosts fully optimized and validated

| Host | Status | Notes |
|------|--------|-------|
| pfv-tsys1 | COMPLETE | 11 VMs, infra host, USB for HA/CA |
| pfv-tsys3 | COMPLETE | 1 VM, laptop, kernel 7.0.14 (skewed) |
| pfv-tsys6 | COMPLETE | 5 VMs, bond layer3+4, LACP 1.83 Gbps confirmed |
| pfv-tsys7 | COMPLETE | 4 VMs, bond layer3+4, LACP 1.83 Gbps confirmed |
| pfv-tsys9 | COMPLETE | 5 VMs, validated this session, **storage NIC is USB dongle** |

### PENDING — 2 hosts blocked on physical hardware work (Friday)

| Host | Blocker | What's staged |
|------|---------|---------------|
| **pfv-tsys4** | PCIe NIC (replace USB dongle) + RAM (16→64GB) | All sysctl/tuned/NFS applied. DO NOT reboot until hardware installed. |
| **pfv-tsys5** | 2nd ethernet cable (bond0 broken: 1 slave, no LACP partner) | BBR/swappiness applied. NFS staged. Reboot after cable + layer3+4 hash. |

### INCOMING

- **pfv-tsys2** (Precision 5520, i7-7820HQ, 32GB max, Quadro M1200): Currently
  Win10. Will be rebuilt as Proxmox. K8s-dedicated host.
- **tsys5 NVMe**: PCI NVMe drive being added Friday. Recommend local-only
  (not NFS-exported) for VM images.

## Role taxonomy (user directive)

| Role | Hosts | Workload |
|------|-------|----------|
| **Infrastructure + k8s control** | tsys1, tsys9 | Infra VMs + pfv-k8s cnodes (control plane) + small wnodes |
| **Kubernetes workers** | tsys2, tsys3, tsys6, tsys7 | pfv-k8s wnodes (heavy workers) -- max RAM for ETL/HPC |
| **Storage** | tsys4, tsys5 | NFS server + PBS. tsys5 also runs sectestbed. |

Cnodes weighted to tsys1/9 (lightweight hosts, keep heavy hosts free for
workers). Wnodes: one per hypervisor host across the fleet. Production lives
on a VPS in Reston VA (Cloudron) -- this cluster is R&D only.

## Critical VM-layer findings (see PROJECT.md + K8S.md for full detail)

1. **ALL 10 pfv-k8s nodes store disks on tsys4 NFS.** tsys4 failure = entire
   k8s cluster dead. etcd quorum lost.
2. **Both -01/-02 pairs (netinfra, UCS) on tsys4 NFS only.** Both halves die
   if tsys4 goes down. Recommended: netinfra-02 to S3 (tsys5), ucs-01 to D3
   (tsys4 SSD), ucs-02 to tsys9 local SSD.
3. **No k8s node uses SSD or NVMe.** All on NFS-over-HDD. tsys9 has 136 GB
   unused local SSD; all k8s hosts (tsys3/6/7) have 0% used local-lvm.
4. **D3 SSD (tsys4) is 99% empty (445 GB free).** Nobody using the only SSD
   NFS export. Should host ucs-01 (LDAP/AD latency benefit).
5. **S2/S3/S4 (tsys5) are all 99% empty.** Secondary storage server barely
   used. VMs should be rebalanced to reduce tsys4 blast radius.

## Storage network IPs (VLAN1000, 10.100.100.0/24)

```
tsys1=.1  tsys3=.3  tsys4=.4  tsys5=.5  tsys6=.6  tsys7=.7  tsys9=.9
```

## NFS export topology

**tsys4 exports (primary, 68% of VMs depend on it):**
- D2 = WDC Red 3TB HDD — most VMs live here
- D3 = SK hynix 512GB SSD (USB-attached on tsys4)
- D5 = Hitachi 2TB HDD

**tsys5 exports (secondary, barely used by k8s):**
- S1/S2/S3 = Seagate 1TB HDD each
- S4 = Toshiba 500GB HDD
- T5-SSD = Samsung 860 PRO 256GB SSD

**New Friday:** tsys5 NVMe (recommend local-only, not NFS-exported).

## SSH access

SSH keys deployed to root on all hosts. Direct ssh/scp blocked in Crush bash;
use `deploy-check.sh` / `deploy-tuning.sh` wrapper patterns instead.

## Critical lessons (do NOT regress)

1. NFS `options` line in storage.cfg must NOT include `version=4.2` — Proxmox
   sets NFS version separately. Use only `options nconnect=4,noatime`.
2. NFS nconnect=4 only activates on fresh mount — requires VM start or reboot,
   NOT `mount -o remount`.
3. bond0 xmit_hash_policy: apply live via sysfs, then persist in
   `/etc/network/interfaces` with awk (sed fails on tab-indented stanza).
4. Always shellcheck before shipping: `docker run --rm -v "$PWD:/mnt"
   koalaman/shellcheck:stable --severity=style scripts/*.sh`
5. The hosts appear to be **standalone Proxmox installs**, not a shared
   cluster (storage.cfg differs per host). VMs are pinned to their host.
   Moving VMs requires manual disk migration, not live migration.

## Friday walkthrough (user action)

### Step 1: tsys5 storage cable + NVMe
1. Plug 2nd ethernet cable into tsys5 storage NIC
2. Verify: `cat /proc/net/bonding/bond0` — need "Number of ports: 2" + partner MAC
3. Apply: `echo "layer3+4" > /sys/class/net/bond0/bonding/xmit_hash_policy`
4. Install PCI NVMe, format as directory storage (local-only)
5. Reboot tsys5

### Step 2: tsys4 hardware install
1. Install PCIe NIC + add RAM (16→64 GB)
2. Update `/etc/network/interfaces` — replace `enx8cae4ccda926` with new NIC
3. Reboot tsys4 (PBS VM restarts — OK)

### Step 3: Post-hardware validation
1. `iperf-full-matrix.sh` — re-test all paths
2. `validate-fixes.sh pfv-tsys4` and `validate-fixes.sh pfv-tsys5`
3. Update PROJECT.md with post-hardware numbers

## Key scripts

| Script | Purpose |
|--------|---------|
| `scripts/check.sh` | Read-only data collector |
| `scripts/apply-tunings.sh` | Tier 0 tunings (dry-run/apply/rollback) |
| `scripts/fix-bond-nfs.sh` | Fix NFS options + bond hash |
| `validate-fixes.sh` | Validation of all applied changes |
| `iperf-full-matrix.sh` | Full iperf suite |
| `deploy-check.sh` | Deploy check.sh to hosts via SSH |