From 5b2a6b01b4faccc636cf5652f780200d635ab988 Mon Sep 17 00:00:00 2001 From: rishabh Date: Sat, 15 Aug 2026 21:37:18 +0800 Subject: [PATCH] Refresh site: nav, identity, Docker preview, first real posts - Simplify nav to Home / Categories / Tags / About, fix placeholder identity/social links (name, email, GitHub + LinkedIn only) - Add Dockerfile + docker-compose.yml for a one-command local preview (docker compose up), since local Ruby is too old for this theme - Enable giscus for comments + emoji reactions, wired to real repo/ category IDs - Add floating Buy Me a Coffee widget and a GitHub follow button - Limit homepage to latest 4 posts with a "See more posts" button (overrides theme's home layout) - Add first real post (NVIDIA Fabric Manager on air-gapped Harvester HGX H200) plus 6 posts redirecting to existing Medium articles - Reorganize _posts/ into YYYY-MM-DD/ subfolders - Add STRUCTURE.md and expand README with local dev + how-to-add-a-post Co-Authored-By: Claude Sonnet 5 --- .dockerignore | 9 + .gitignore | 1 + Dockerfile | 17 + README.md | 58 ++ STRUCTURE.md | 63 ++ _config.yml | 25 +- _data/contact.yml | 36 +- _includes/footer.html | 63 ++ _layouts/home.html | 144 ++++ _posts/.placeholder | 1 - ...phere-vm-to-kubevirt-vm-migration-guide.md | 10 + ...nclaw-and-virtualisation-infrastructure.md | 10 + ...7-04-integrating-harvester-with-rancher.md | 10 + ...ployments-with-packer-and-ova-templates.md | 10 + ...phere-vm-notes-using-python-and-pyvmomi.md | 10 + ...accelerated-ai-inference-with-llama-cpp.md | 10 + ...c-manager-air-gapped-harvester-hgx-h200.md | 668 ++++++++++++++++++ _tabs/about.md | 12 +- _tabs/archives.md | 5 - docker-compose.yml | 10 + 20 files changed, 1118 insertions(+), 54 deletions(-) create mode 100644 .dockerignore create mode 100644 Dockerfile create mode 100644 STRUCTURE.md create mode 100644 _includes/footer.html create mode 100644 _layouts/home.html delete mode 100644 _posts/.placeholder create mode 100644 _posts/2026-06-06/2026-06-06-vsphere-vm-to-kubevirt-vm-migration-guide.md create mode 100644 _posts/2026-06-20/2026-06-20-openclaw-and-virtualisation-infrastructure.md create mode 100644 _posts/2026-07-04/2026-07-04-integrating-harvester-with-rancher.md create mode 100644 _posts/2026-07-18/2026-07-18-accelerate-vm-deployments-with-packer-and-ova-templates.md create mode 100644 _posts/2026-08-01/2026-08-01-get-vsphere-vm-notes-using-python-and-pyvmomi.md create mode 100644 _posts/2026-08-10/2026-08-10-gpu-accelerated-ai-inference-with-llama-cpp.md create mode 100644 _posts/2026-08-12/2026-08-12-installing-nvidia-fabric-manager-air-gapped-harvester-hgx-h200.md delete mode 100644 _tabs/archives.md create mode 100644 docker-compose.yml diff --git a/.dockerignore b/.dockerignore new file mode 100644 index 0000000..5aa2070 --- /dev/null +++ b/.dockerignore @@ -0,0 +1,9 @@ +.git +_site +.jekyll-cache +.jekyll-metadata +vendor +.bundle +Gemfile.lock +node_modules +assets/lib diff --git a/.gitignore b/.gitignore index 7dd7cef..f117f5c 100644 --- a/.gitignore +++ b/.gitignore @@ -16,6 +16,7 @@ node_modules package-lock.json # IDE configurations +.claude .idea .vscode/* !.vscode/settings.json diff --git a/Dockerfile b/Dockerfile new file mode 100644 index 0000000..e2d2697 --- /dev/null +++ b/Dockerfile @@ -0,0 +1,17 @@ +FROM ruby:3.2-slim + +RUN apt-get update -qq && apt-get install -y --no-install-recommends \ + build-essential \ + git \ + && rm -rf /var/lib/apt/lists/* + +WORKDIR /srv/jekyll + +COPY Gemfile ./ +RUN bundle install + +COPY . . + +EXPOSE 4000 + +CMD ["bundle", "exec", "jekyll", "serve", "--host", "0.0.0.0", "--port", "4000"] diff --git a/README.md b/README.md index f8f4c5b..1f014a1 100644 --- a/README.md +++ b/README.md @@ -5,3 +5,61 @@ Personal blog covering platform engineering, Kubernetes, and AI/ML infrastructur Built with [Jekyll](https://jekyllrb.com) + [Chirpy](https://github.com/cotes2020/jekyll-theme-chirpy), hosted on GitHub Pages. 🌐 [allexistence.github.io](https://allexistence.github.io) + +## 1. Local development + +Requires [Docker](https://www.docker.com/) — no local Ruby/Jekyll install needed. + +```bash +docker compose up +``` + +Open [http://localhost:4000](http://localhost:4000). Edit any file and refresh the page — Jekyll +auto-rebuilds on save. If you edit `_config.yml`, restart instead of just refreshing: + +```bash +docker compose restart +``` + +Stop the server with `Ctrl+C`, or `docker compose down` if it's running in the background. If you +add a gem to the `Gemfile`, rebuild the image: + +```bash +docker compose up --build +``` + +## 2. How to add a post + +Create a new file in [`_posts/`](_posts/), inside a folder named after the post's date, e.g.: + +``` +_posts/YYYY-MM-DD/YYYY-MM-DD-a-short-slug.md +``` + +The date must appear in both the folder name (for organization) and the filename itself — Jekyll +only recognizes a post by its filename, not its folder, so the date prefix on the file is required +either way. + +Add front matter at the top of the file: + +```yaml +--- +title: "Post Title" +date: 2026-08-15 09:00:00 +0800 +categories: [Category Name] +tags: [tag-one, tag-two, tag-three] +--- +``` + +Then write the post in Markdown below the front matter. A few notes: + +- **Categories** are broad sections (shown on the `/categories/` page) — keep each post to one or + two. +- **Tags** are finer-grained keywords (shown on the `/tags/` page) — reuse existing tags where they + fit so the tag cloud stays useful; check `/tags/` for what already exists. +- The homepage shows the 4 most recent posts with a "See more posts" button — no extra config + needed, new posts just appear at the top automatically, newest first. +- Comments and emoji reactions are enabled by default on every post (via giscus) — nothing to turn + on per post. +- To link out to an externally-hosted post instead of writing one here, see any of the existing + Medium-redirect posts in `_posts/` for the pattern (a ` diff --git a/_layouts/home.html b/_layouts/home.html new file mode 100644 index 0000000..389b49c --- /dev/null +++ b/_layouts/home.html @@ -0,0 +1,144 @@ +--- +layout: default +--- + +{% include lang.html %} + +{% assign all_pinned = site.posts | where: 'pin', 'true' %} +{% assign all_normal = site.posts | where_exp: 'item', 'item.pin != true and item.hidden != true' %} + +{% assign posts = '' | split: '' %} + + + +{% assign visible_start = paginator.page | minus: 1 | times: paginator.per_page %} +{% assign visible_end = visible_start | plus: paginator.per_page %} + +{% if all_pinned.size > visible_start %} + {% if all_pinned.size > visible_end %} + {% assign pinned_size = paginator.per_page %} + {% else %} + {% assign pinned_size = all_pinned.size | minus: visible_start %} + {% endif %} + + {% for i in (visible_start..all_pinned.size) limit: pinned_size %} + {% assign posts = posts | push: all_pinned[i] %} + {% endfor %} +{% else %} + {% assign pinned_size = 0 %} +{% endif %} + + + +{% assign normal_size = paginator.posts | size | minus: pinned_size %} + +{% if normal_size > 0 %} + {% if pinned_size > 0 %} + {% assign normal_start = 0 %} + {% else %} + {% assign normal_start = visible_start | minus: all_pinned.size %} + {% endif %} + + {% assign normal_end = normal_start | plus: normal_size | minus: 1 %} + + {% for i in (normal_start..normal_end) %} + {% assign posts = posts | push: all_normal[i] %} + {% endfor %} +{% endif %} + +
+ {% for post in posts %} +
+ + {% assign card_body_col = '12' %} + + {% if post.image %} + {% assign src = post.image.path | default: post.image %} + + {% if post.media_subpath %} + {% unless src contains '://' %} + {% assign src = post.media_subpath + | append: '/' + | append: src + | replace: '///', '/' + | replace: '//', '/' + %} + {% endunless %} + {% endif %} + + {% if post.image.lqip %} + {% assign lqip = post.image.lqip %} + + {% if post.media_subpath %} + {% unless lqip contains 'data:' %} + {% assign lqip = post.media_subpath + | append: '/' + | append: lqip + | replace: '///', '/' + | replace: '//', '/' + %} + {% endunless %} + {% endif %} + + {% assign lqip_attr = 'lqip="' | append: lqip | append: '"' %} + {% endif %} + + {% assign alt = post.image.alt | xml_escape | default: 'Preview Image' %} + +
+ {{ alt }} +
+ + {% assign card_body_col = '7' %} + {% endif %} + +
+
+

{{ post.title }}

+ +
+

{% include post-summary.html %}

+
+ +
+
+ + + {% include datetime.html date=post.date lang=lang %} + + + {% if post.categories.size > 0 %} + + + {% for category in post.categories %} + {{ category }} + {%- unless forloop.last -%},{%- endunless -%} + {% endfor %} + + {% endif %} +
+ + {% if post.pin %} +
+ + {{ site.data.locales[lang].post.pin_prompt }} +
+ {% endif %} +
+ +
+ +
+ +
+ {% endfor %} +
+ + +{% if paginator.next_page %} +
+ + See more posts + +
+{% endif %} diff --git a/_posts/.placeholder b/_posts/.placeholder deleted file mode 100644 index 8b13789..0000000 --- a/_posts/.placeholder +++ /dev/null @@ -1 +0,0 @@ - diff --git a/_posts/2026-06-06/2026-06-06-vsphere-vm-to-kubevirt-vm-migration-guide.md b/_posts/2026-06-06/2026-06-06-vsphere-vm-to-kubevirt-vm-migration-guide.md new file mode 100644 index 0000000..0ab4563 --- /dev/null +++ b/_posts/2026-06-06/2026-06-06-vsphere-vm-to-kubevirt-vm-migration-guide.md @@ -0,0 +1,10 @@ +--- +title: "vSphere VM to KubeVirt VM: Complete Migration Guide" +date: 2026-06-06 09:00:00 +0800 +categories: [Virtualization] +tags: [kubevirt, vsphere, migration, harvester] +--- + + + +Redirecting to Medium... [continue reading →](https://medium.com/@0.all_existence.0/vsphere-vm-to-kubevirt-vm-complete-migration-guide-959c90ef5950) diff --git a/_posts/2026-06-20/2026-06-20-openclaw-and-virtualisation-infrastructure.md b/_posts/2026-06-20/2026-06-20-openclaw-and-virtualisation-infrastructure.md new file mode 100644 index 0000000..e06e879 --- /dev/null +++ b/_posts/2026-06-20/2026-06-20-openclaw-and-virtualisation-infrastructure.md @@ -0,0 +1,10 @@ +--- +title: "OpenClaw and Virtualisation Infrastructure: Talking to Harvester HCI Like a Human" +date: 2026-06-20 09:00:00 +0800 +categories: [Virtualization] +tags: [harvester, automation, ai] +--- + + + +Redirecting to Medium... [continue reading →](https://medium.com/@0.all_existence.0/openclaw-and-virtualisation-infrastructure-talking-to-harvester-hci-like-a-human-52fb4a502f10) diff --git a/_posts/2026-07-04/2026-07-04-integrating-harvester-with-rancher.md b/_posts/2026-07-04/2026-07-04-integrating-harvester-with-rancher.md new file mode 100644 index 0000000..63edcdf --- /dev/null +++ b/_posts/2026-07-04/2026-07-04-integrating-harvester-with-rancher.md @@ -0,0 +1,10 @@ +--- +title: "Integrating Harvester with Rancher" +date: 2026-07-04 09:00:00 +0800 +categories: [Virtualization] +tags: [harvester, rancher, kubernetes] +--- + + + +Redirecting to Medium... [continue reading →](https://medium.com/@0.all_existence.0/integrating-harvester-with-rancher-1bc417ebb538) diff --git a/_posts/2026-07-18/2026-07-18-accelerate-vm-deployments-with-packer-and-ova-templates.md b/_posts/2026-07-18/2026-07-18-accelerate-vm-deployments-with-packer-and-ova-templates.md new file mode 100644 index 0000000..8148f81 --- /dev/null +++ b/_posts/2026-07-18/2026-07-18-accelerate-vm-deployments-with-packer-and-ova-templates.md @@ -0,0 +1,10 @@ +--- +title: "Accelerate VM Deployments with Packer and OVA Templates in vSphere" +date: 2026-07-18 09:00:00 +0800 +categories: [Automation] +tags: [packer, vsphere, ova, iac] +--- + + + +Redirecting to Medium... [continue reading →](https://medium.com/@0.all_existence.0/accelerate-vm-deployments-with-packer-and-ova-templates-in-vsphere-e55303cb8eae) diff --git a/_posts/2026-08-01/2026-08-01-get-vsphere-vm-notes-using-python-and-pyvmomi.md b/_posts/2026-08-01/2026-08-01-get-vsphere-vm-notes-using-python-and-pyvmomi.md new file mode 100644 index 0000000..600b1e0 --- /dev/null +++ b/_posts/2026-08-01/2026-08-01-get-vsphere-vm-notes-using-python-and-pyvmomi.md @@ -0,0 +1,10 @@ +--- +title: "Get vSphere VM Notes Using Python and PyVmomi" +date: 2026-08-01 09:00:00 +0800 +categories: [Automation] +tags: [python, pyvmomi, vsphere] +--- + + + +Redirecting to Medium... [continue reading →](https://medium.com/@0.all_existence.0/use-pyvmomi-to-read-vm-notes-annotations-from-vsphere-f69ee92ba2e3) diff --git a/_posts/2026-08-10/2026-08-10-gpu-accelerated-ai-inference-with-llama-cpp.md b/_posts/2026-08-10/2026-08-10-gpu-accelerated-ai-inference-with-llama-cpp.md new file mode 100644 index 0000000..b2c9615 --- /dev/null +++ b/_posts/2026-08-10/2026-08-10-gpu-accelerated-ai-inference-with-llama-cpp.md @@ -0,0 +1,10 @@ +--- +title: "GPU Accelerated AI Inference with llama.cpp in a Linux Container on macOS" +date: 2026-08-10 09:00:00 +0800 +categories: [AI-ML] +tags: [llama.cpp, gpu, ai-inference, macos] +--- + + + +Redirecting to Medium... [continue reading →](https://medium.com/@0.all_existence.0/gpu-accelerated-ai-inference-with-llama-cpp-in-a-linux-container-on-macos-37b6557f5d59) diff --git a/_posts/2026-08-12/2026-08-12-installing-nvidia-fabric-manager-air-gapped-harvester-hgx-h200.md b/_posts/2026-08-12/2026-08-12-installing-nvidia-fabric-manager-air-gapped-harvester-hgx-h200.md new file mode 100644 index 0000000..a6fd5d7 --- /dev/null +++ b/_posts/2026-08-12/2026-08-12-installing-nvidia-fabric-manager-air-gapped-harvester-hgx-h200.md @@ -0,0 +1,668 @@ +--- +title: "Installing NVIDIA Fabric Manager on an Air-Gapped Harvester HGX H200 Host" +date: 2026-08-12 09:00:00 +0800 +categories: [GPU Infrastructure] +tags: [nvidia, fabric-manager, hgx, h200, nvswitch, harvester, kubevirt, gpu, air-gapped, vfio] +--- + +Getting CUDA working inside passthrough VMs on an 8× H200 SXM HGX system running Harvester, +where the host OS is immutable and the environment has no internet access and no NVIDIA vGPU licence. + +--- + +## Part 1 — Background: the NVIDIA concepts that matter here + +### NVLink and NVSwitch + +On an HGX baseboard, the GPUs are not only connected by PCIe. They also have **NVLink** ports — +a much faster, GPU-to-GPU interconnect used for peer-to-peer memory access and collective +operations in multi-GPU training. + +On small systems, NVLink is a fixed mesh of direct GPU-to-GPU cables. On an HGX baseboard, every +GPU's NVLink ports instead connect to **NVSwitch** — a crossbar switch ASIC that routes NVLink +traffic between any pair of GPUs at full bandwidth. An 8-GPU HGX board typically carries four +NVSwitch ASICs forming a single fabric domain across all eight GPUs. + +Two things follow from this, and they drive everything else in this document: + +1. **NVSwitch is not a per-GPU resource.** It is shared infrastructure belonging to the whole + baseboard. It has its own routing tables and memory-mapped address space, and appears as its + own PCI device — distinct from the GPUs. +2. **NVSwitch is not a PCIe switch.** It switches NVLink traffic. The PCIe switches on the board + (e.g. Broadcom PEX-series) are a completely separate layer, and they are what determines your + IOMMU groupings. Don't conflate the two — they are different fabrics with different constraints. + +> **Further reading** +> - [NVIDIA NVLink and NVSwitch overview](https://www.nvidia.com/en-us/data-center/nvlink/) — what the interconnect is and why it exists +> - [NVIDIA HGX Software User Guide](https://docs.nvidia.com/datacenter/tesla/hgx-software-guide/index.html) — the full software stack for an HGX baseboard, bottom to top + +### Fabric Manager + +The NVSwitch ASICs do not configure themselves. **Fabric Manager (FM)** is a host-side service +that: + +- discovers the NVSwitches and GPUs on the baseboard, +- loads the correct topology file for the board, +- programs the switch routing tables, +- and reports fabric health. + +Until FM has run successfully, GPUs on an NVSwitch system report: + +``` +Fabric State : In Progress +``` + +and CUDA refuses to initialise, typically with: + +``` +Error 802: system not yet initialized +``` + +FM depends on two other pieces: + +| Component | Role | +|---|---| +| NVIDIA kernel driver | Provides `nvidia-nvswitch` — the kernel-side driver that claims the NVSwitch PCI devices | +| `libnvidia-nscq` | NSCQ = NVSwitch Configuration and Query. The library FM uses to talk to the switches | + +So the dependency chain is strictly: **driver → NSCQ → Fabric Manager**. Installing FM alone +achieves nothing; it will start, fail to query NVSwitch device information, and exit. + +FM's four documented responsibilities are worth internalising, since they explain every symptom in +this document: + +1. Coordinate with the NVSwitch driver to initialise and train switch-to-switch NVLinks +2. Coordinate with the GPU driver to initialise and train switch-to-GPU NVLinks +3. Configure routing among NVSwitch ports +4. Monitor the fabric for NVLink and NVSwitch errors + +> **Further reading** +> - [NVIDIA Fabric Manager User Guide](https://docs.nvidia.com/datacenter/tesla/fabric-manager-user-guide/index.html) — the primary reference for everything in this document +> - [Fabric Manager config options](https://docs.nvidia.com/datacenter/tesla/fabric-manager-user-guide/contents.html) — full table of contents, including config options, startup options and the service file +> - [Fabric Manager Client (GitHub)](https://github.com/NVIDIA/Fabric-Manager-Client) — CLI for the partition-management API used in Shared NVSwitch mode + +### Where each piece runs in a virtualised setup + +This is the single most important design point, and getting it wrong is a very common mistake. + +| Component | Host | Guest VM | +|---|---|---| +| NVIDIA kernel driver (for NVSwitch) | ✅ | — | +| Fabric Manager + NSCQ | ✅ | ❌ **never** | +| GPU driver | — | ✅ | +| CUDA toolkit, PyTorch, workloads | — | ✅ | + +A guest VM that receives individual GPUs via PCI passthrough **cannot see the NVSwitch hardware** +— and should not. Running FM inside such a guest fails immediately, because there is no NVSwitch +device for it to query. + +The handshake between the two sides happens through the GPU hardware itself: host-side FM programs +the fabric, and when the guest's GPU driver initialises, it reads that state from the GPU and +reports `Fabric State: Completed`. + +### The two supported virtualisation models + +| Model | GPUs | NVSwitch | Fabric Manager | Use when | +|---|---|---|---|---| +| **Full baseboard passthrough** | All 8 to one VM | Also passed through | Runs **inside the guest** | One workload needs all 8 GPUs with full NVLink | +| **Shared NVSwitch** | Passed through individually to different VMs | Stays host-owned | Runs **on the host** | GPUs split across multiple VMs | + +Passing through *some* GPUs plus the NVSwitch is not a valid configuration. The switch is either +entirely host-owned, or it goes to a single VM along with every GPU on the board. + +This document covers the **Shared NVSwitch** model. + +> **Further reading** +> - [Full Passthrough Virtualization Model](https://docs.nvidia.com/datacenter/tesla/fabric-manager-user-guide/index.html#full-passthrough-virtualization-model) — supported VM configurations for 1, 2, 4, 8 and 16 GPUs, and their limitations +> - [Shared NVSwitch Virtualization Model](https://docs.nvidia.com/datacenter/tesla/fabric-manager-user-guide/index.html#shared-nvswitch-virtualization-model) — service VM design, guest lifecycle, and the partition APIs +> - [Bare Metal Mode](https://docs.nvidia.com/datacenter/tesla/fabric-manager-user-guide/index.html#bare-metal-mode) — the `FABRIC_MODE=0` behaviour this setup ended up relying on + +--- + +## Part 2 — The problem + +**Symptom (inside the guest VM):** + +``` +Error 802: system not yet initialized +torch.cuda.is_available() -> False +``` + +``` +Fabric + State : In Progress + Status : N/A +GPU Fabric GUID : N/A +``` + +**First wrong turn:** Fabric Manager had been installed *inside the guest VM*, where it failed with: + +``` +request to query NVSwitch device information from NVSwitch driver ... failed +``` + +That is correct behaviour — a passthrough guest has no NVSwitch. FM was in the wrong place. + +**Actual root cause**, found by inspecting the host: + +```bash +lspci -k +``` + +``` +xx:00.0 Bridge: NVIDIA Corporation GH100 [H100 NVSwitch] (rev a1) + Subsystem: NVIDIA Corporation Device 1796 + <-- no "Kernel driver in use" line at all +``` + +All four NVSwitch bridges had **no kernel driver bound**. Meanwhile the GPUs were correctly bound +to `vfio-pci` for passthrough, and NVMe was on `nvme`. Only the switches were orphaned. + +No driver on the switches → FM cannot initialise the fabric → every passthrough GPU waits forever +on a handshake that never comes. + +--- + +## Part 3 — Approaches that did not work + +Documented so they are not retried. + +| Attempt | Outcome | +|---|---| +| Harvester `nvidia-driver-toolkit` add-on | Requires a **licensed vGPU/GRID `.run` driver** from NVIDIA's licensing portal. Also vGPU-specific — the documentation makes no mention of NVSwitch or Fabric Manager. Not applicable to full PCI passthrough. | +| NVIDIA Container Toolkit | Wrong layer entirely. It exposes GPUs to *containers* and explicitly assumes a working host driver already exists. Irrelevant when GPUs go straight into VMs via VFIO. | +| `zypper install` on host | `The target filesystem is mounted as read-only.` | +| `transactional-update pkg install` | `command not found` — removed from this build. | +| `mount -o remount,rw /` | `cannot remount /dev/loopN read-write, is write-protected` — the root is a loop-mounted OS **image**, not merely a read-only mount flag. | +| `.run` driver installer | Designed for a normal writable filesystem; incompatible with an immutable/transactional root. | +| Passing NVSwitch through to a guest | Breaks the shared-fabric model; guest gains control over routing affecting GPUs owned by other VMs. | + +### Why no package can be installed + +The host is SUSE Linux Micro with an elemental-style immutable root. From `/proc/cmdline`: + +``` +root=LABEL=COS_STATE cos-img/filename=/cOS/active.img +rd.cos.mount=LABEL=COS_OEM:/oem +rd.cos.mount=LABEL=COS_PERSISTENT:/usr/local +``` + +The root filesystem is a read-only image file. But note the last line: **`/usr/local` is a +writable, persistent partition.** That is the opening. + +> **Further reading** +> - [Harvester PCI Devices add-on](https://docs.harvesterhci.io/v1.4/advanced/addons/pcidevices/) — how `PCIDevice` / `PCIDeviceClaim` bind host devices to `vfio-pci` +> - [`harvester/pcidevices` controller (GitHub)](https://github.com/harvester/pcidevices) — the controller doing the runtime binding, and the CRD shapes +> - [Harvester NVIDIA driver toolkit add-on](https://docs.harvesterhci.io/v1.8/advanced/addons/nvidiadrivertoolkit/) — the vGPU-oriented add-on, and why it doesn't apply here +> - [Harvester CloudInit CRD](https://docs.harvesterhci.io/v1.8/advanced/cloudinitcrd/) — the supported way to persist host-level config on an immutable OS +> - [NVIDIA Container Toolkit install guide](https://docs.nvidia.com/datacenter/cloud-native/container-toolkit/latest/install-guide.html) — note its prerequisite that a host driver already exists; it is a container-layer tool, not a passthrough one + +--- + +## Part 4 — The approach that worked + +> Kernel modules do not have to be installed to be loaded. `insmod` accepts any file path. +> So: extract the RPMs into the writable partition and load the module by hand. + +No package installation, no filesystem remount, no OS modification. + +--- + +## Part 5 — Phase 1: obtaining the packages (air-gapped) + +Performed on a separate staging VM that has internet access and Docker. The staging VM ran Ubuntu, +which has no `zypper`, so a SUSE container was used to resolve dependencies properly rather than +scraping HTML directory listings. + +### 5.1 Start a SUSE container + +```bash +mkdir -p rpms +docker run -it --rm -v $(pwd)/rpms:/rpms registry.opensuse.org/opensuse/leap:16.0 bash +``` + +### 5.2 Add the NVIDIA repositories + +```bash +zypper ar -G https://download.nvidia.com/suse/sle16/ nvidia-gfx +zypper ar -G https://developer.download.nvidia.com/compute/cuda/repos/sles15/x86_64/ nvidia-cuda +zypper refresh +``` + +### 5.3 Find what actually exists + +```bash +zypper se -s nvidia-open-driver-G06-signed-kmp +zypper se -s nvidia-fabricmanager +zypper se -s libnvidia-nscq +``` + +**Key discovery — the packages are spread across three repositories:** + +| Package | Repository | +|---|---| +| `nvidia-open-driver-G06-signed-kmp-default` — *the actual kernel module* | **Leap `repo-oss`** (the distribution repo) | +| `nvidia-open-driver-G06-signed-kmp-meta` — a 36 KB pointer only | `nvidia-gfx` | +| `nvidia-fabricmanager`, `libnvidia-nscq` | `nvidia-cuda` | +| `nvidia-compute-utils-G06`, `nvidia-common-G06`, `nvidia-compute-G06` | `nvidia-gfx` / `nvidia-cuda` | + +NVIDIA's SUSE repo ships **only** userspace packages and meta-packages. SUSE builds and signs the +kernel module itself, so the real binary comes from the distribution repository. Scraping NVIDIA's +repo alone will never find it. + +### 5.4 Choosing a version + +Two constraints must hold simultaneously: + +1. The version must exist in **all** the repos involved — FM must match the driver version exactly, + or it refuses to attach. +2. The kernel module package (KMP) must be **kABI-compatible** with the running host kernel. + +The KMP filename encodes the kernel it was built against, e.g.: + +``` +nvidia-open-driver-G06-signed-kmp-default-_k6.12.0_-... +``` + +Candidate matrix (host kernel ABI was `160000.28`): + +| Driver | Built against | FM + NSCQ available? | Verdict | +|---|---|---|---| +| 580.159.03 | `160000.29` — **newer than host** | yes | risky | +| 580.126.18 | `160000.26` | **no** | unusable | +| **580.126.09** | `160000.9` — older, same codestream | **yes** | **chosen** | +| 580.119.02 | `160000.7` | no | unusable | + +**Rule of thumb:** within a single SUSE codestream, kernel ABI is stable, so a module built against +an *older* kernel in that stream loads fine on a newer one. The reverse direction is the risky one — +a module built against a newer kernel may reference symbols the running kernel does not have. + +### 5.5 Download without installing + +```bash +zypper --pkg-cache-dir /rpms install -y --download-only \ + nvidia-open-driver-G06-signed-kmp-default=580.126.09_k6.12.0_160000.9-160000.1.1 \ + nvidia-compute-utils-G06=580.126.09-1 \ + nvidia-fabricmanager=580.126.09-1 \ + libnvidia-nscq=580.126.09-1 +exit +``` + +Syntax notes: + +- The version goes after `=`. Appending it to the package name fails. +- `nvidia-fabricmanager` and `libnvidia-nscq` have **no** `-580` branch suffix; modern packages + carry the branch in the version field. + +### ⚠️ 5.6 Exclude the kernel package + +The resolver pulls **`kernel-default`** (a full kernel, newer than the host's) because the container +has no kernel installed. This must **never** reach the host — the platform manages its own kernel, +and replacing it out-of-band risks breaking the node. + +--- + +## Part 6 — Phase 2: internal repository + +```bash +mkdir -p nvidia-repo +find rpms -name '*.rpm' ! -name 'kernel-default*' -exec cp {} nvidia-repo/ \; +ls nvidia-repo | grep kernel # MUST return nothing +createrepo_c nvidia-repo/ +cd nvidia-repo && python3 -m http.server 8000 +``` + +Verify reachability from the GPU host: + +```bash +curl -sI http://:8000/repodata/repomd.xml # expect 200 OK +``` + +> A `python3 -m http.server` dies with the SSH session. Use nginx for anything long-lived. + +--- + +## Part 7 — Phase 3: load the driver on the host + +### 7.1 Extract into the writable partition + +```bash +mkdir -p /usr/local/nvidia && cd /usr/local/nvidia +curl -O http://:8000/nvidia-open-driver-G06-signed-kmp-default-580.126.09_k6.12.0_160000.9-160000.1.1.x86_64.rpm +curl -O http://:8000/nvidia-fabricmanager-580.126.09-1.x86_64.rpm +curl -O http://:8000/libnvidia-nscq-580.126.09-1.x86_64.rpm +curl -O http://:8000/nvidia-modprobe-580.126.09-160000.22.1.x86_64.rpm +for f in *.rpm; do rpm2cpio $f | cpio -idm; done +``` + +`rpm2cpio | cpio -idm` unpacks an RPM's contents into the current directory without touching the +RPM database or the system. + +### 7.2 Decompress and load the module + +SUSE ships kernel modules zstd-compressed; `insmod` needs them decompressed. + +```bash +cd /usr/local/nvidia/usr/lib/modules/6.12.0-160000.9-default/updates/ +zstd -d nvidia.ko.zst +insmod ./nvidia.ko +dmesg | tail -20 +``` + +Success: + +``` +NVRM: loading NVIDIA UNIX Open Kernel Module for x86_64 580.126.09 Release Build +``` + +No symbol or version errors — the kABI compatibility assumption held. + +> If Secure Boot is enforced, an unenrolled module signature will be rejected here. Check with +> `mokutil --sb-state`, or `dmesg | grep -i "secure boot"` if `mokutil` is absent. + +### 7.3 Verify driver binding — both conditions must hold + +```bash +lspci -k -s # e.g. 09:00.0 +lspci -k -s # e.g. 23:00.0 +``` + +``` +Bridge: NVIDIA Corporation GH100 [H100 NVSwitch] + Kernel driver in use: nvidia-nvswitch <-- switch claimed ✅ +3D controller: NVIDIA Corporation GH100 [H200 SXM 141GB] + Kernel driver in use: vfio-pci <-- passthrough intact ✅ +``` + +If a GPU shows `nvidia`, **stop**. The driver has stolen a passthrough device. See Part 10. + +--- + +## Part 8 — Phase 4: create NVSwitch device nodes + +There are no udev rules for these on a minimal host, and `nvidia-modprobe -c 0` will not help — it +creates *GPU* nodes, and all GPUs are vfio-bound and invisible to the NVIDIA driver. + +Find the character device major number and confirm the switches registered: + +```bash +cat /proc/devices | grep -i nvidia +ls /proc/driver/nvidia-nvswitch/devices/ +``` + +``` +507 nvidia-nvswitch +0000:09:00.0 0000:0a:00.0 0000:0b:00.0 0000:0c:00.0 +``` + +Create the nodes — one per switch, plus a control node at minor 255: + +```bash +MAJOR=$(awk '/nvidia-nvswitch/{print $1}' /proc/devices) +mknod -m 666 /dev/nvidia-nvswitchctl c $MAJOR 255 +for i in 0 1 2 3; do mknod -m 666 /dev/nvidia-nvswitch$i c $MAJOR $i; done +ls -la /dev/nvidia-nvswitch* +``` + +> Read the major from `/proc/devices` rather than hardcoding it — dynamic majors can change +> between boots. + +--- + +## Part 9 — Phase 5: configure and start Fabric Manager + +The stock config references absolute paths under `/usr/share` and `/var`, which don't exist here. +Copy it and repoint everything at the extracted tree. + +```bash +cd /usr/local/nvidia +cp ./usr/share/nvidia/nvswitch/fabricmanager.cfg fm.cfg +sed -i 's|^TOPOLOGY_FILE_PATH=.*|TOPOLOGY_FILE_PATH=/usr/local/nvidia/usr/share/nvidia/nvswitch|' fm.cfg +sed -i 's|^LOG_FILE_NAME=.*|LOG_FILE_NAME=/usr/local/nvidia/fabricmanager.log|' fm.cfg +sed -i 's|^STATE_FILE_NAME=.*|STATE_FILE_NAME=/usr/local/nvidia/fabricmanager.state|' fm.cfg +sed -i 's|^DAEMONIZE=.*|DAEMONIZE=0|' fm.cfg +``` + +The topology directory contains a file per supported board; the HGX H100/H200 baseboard uses +`dgxh100_hgxh100_topology`. FM selects it automatically once the path is correct. + +Start it: + +```bash +export LD_LIBRARY_PATH=/usr/local/nvidia/usr/lib64:/usr/local/nvidia/usr/lib:$LD_LIBRARY_PATH +./usr/bin/nv-fabricmanager -c /usr/local/nvidia/fm.cfg +``` + +``` +Successfully configured all the available NVSwitches to route GPU NVLink traffic. +NVLink Peer-to-Peer support will be enabled once the GPUs are successfully +registered with the NVLink fabric. +``` + +### A note on FABRIC_MODE + +| Value | Meaning | +|---|---| +| `0` | Bare metal — FM expects to see the GPUs itself | +| `1` | Shared NVSwitch — FM configures switches, then waits for a hypervisor service to call its partition-activation API | + +**`FABRIC_MODE=0` worked**, even though the GPUs are vfio-bound and invisible to the host driver. +The switches initialise, and each GPU registers with the fabric when its driver starts inside its +guest. Mode `1` was *not* required — which matters, because it expects a hypervisor integration +that KubeVirt-based platforms do not provide out of the box. + +--- + +## Part 10 — Persistence + +Nothing loaded at runtime survives a reboot: the module, the device nodes and the FM process all +disappear. Only the extracted files under `/usr/local` persist. + +### 10.1 Startup script + +```bash +cat > /usr/local/nvidia/start-fm.sh << 'EOF' +#!/bin/bash +set -e +cd /usr/local/nvidia +# 1. Load the NVIDIA kernel module (claims the NVSwitch bridges) +lsmod | grep -q '^nvidia ' || \ + insmod ./usr/lib/modules/6.12.0-160000.9-default/updates/nvidia.ko +# 2. Create NVSwitch device nodes +MAJOR=$(awk '/nvidia-nvswitch/{print $1}' /proc/devices) +[ -e /dev/nvidia-nvswitchctl ] || mknod -m 666 /dev/nvidia-nvswitchctl c $MAJOR 255 +for i in 0 1 2 3; do + [ -e /dev/nvidia-nvswitch$i ] || mknod -m 666 /dev/nvidia-nvswitch$i c $MAJOR $i +done +# 3. Start Fabric Manager +export LD_LIBRARY_PATH=/usr/local/nvidia/usr/lib64:/usr/local/nvidia/usr/lib:$LD_LIBRARY_PATH +exec ./usr/bin/nv-fabricmanager -c /usr/local/nvidia/fm.cfg +EOF +chmod +x /usr/local/nvidia/start-fm.sh +``` + +### 10.2 systemd unit + +```bash +cat > /etc/systemd/system/nvidia-fabricmanager-local.service << 'EOF' +[Unit] +Description=NVIDIA Fabric Manager (local extracted) +After=network.target + +[Service] +Type=simple +ExecStart=/usr/local/nvidia/start-fm.sh +Restart=on-failure +RestartSec=10 + +[Install] +WantedBy=multi-user.target +EOF +systemctl daemon-reload +systemctl enable --now nvidia-fabricmanager-local +systemctl status nvidia-fabricmanager-local +``` + +> **`DAEMONIZE=0` is required** (set in Part 9). FM daemonises by default, which makes a +> `Type=simple` unit report `inactive (dead)` moments after start — systemd sees the parent exit +> while FM keeps running untracked, and `Restart=on-failure` becomes useless. With `DAEMONIZE=0` +> the service shows `active (running)` and logs land in journald. +> (Alternative: keep `DAEMONIZE=1` and use `Type=forking`.) + +### 10.3 Surviving OS upgrades + +On an immutable OS, `/etc` may be reset from the image at boot, and is definitely replaced on an OS +upgrade. To make the unit file reappear every boot, write it via the platform's own cloud-init +mechanism (which writes into the persistent `/oem` partition) rather than relying on the manual +`/etc` write: + +```yaml +apiVersion: node.harvesterhci.io/v1beta1 +kind: CloudInit +metadata: + name: nvidia-fabricmanager +spec: + matchSelector: + kubernetes.io/hostname: + filename: 90-nvidia-fabricmanager.yaml + contents: | + stages: + boot: + - name: "install fabric manager service" + files: + - path: /etc/systemd/system/nvidia-fabricmanager-local.service + permissions: 0644 + content: | + [Unit] + Description=NVIDIA Fabric Manager (local extracted) + After=network.target + [Service] + Type=simple + ExecStart=/usr/local/nvidia/start-fm.sh + Restart=on-failure + RestartSec=10 + [Install] + WantedBy=multi-user.target + commands: + - systemctl daemon-reload + - systemctl enable --now nvidia-fabricmanager-local.service + paused: false +``` + +Verify it landed without rebooting: + +```bash +kubectl get cloudinit +ls -la /oem/ # the rendered file should appear here +elemental run-stage boot # re-execute the boot stage now +systemctl status nvidia-fabricmanager-local +``` + +### 10.4 Protecting the passthrough binding + +If GPU→`vfio-pci` binding is performed at runtime by a controller pod rather than at boot, there is +now a race: the `nvidia` driver exists on the host and may claim a GPU before the controller binds +it. If `lspci -k` ever shows a GPU on `nvidia` instead of `vfio-pci` after a reboot, pin it: + +``` +# /etc/modprobe.d/10-vfio-gpu-pin.conf +options vfio-pci ids=10de:2335 +softdep nvidia pre: vfio-pci +``` + +`10de:2335` is the H200 SXM PCI ID. Do **not** add the NVSwitch ID here — the switches must be +claimed by `nvidia`. + +--- + +## Part 11 — Verification + +### Host + +```bash +systemctl status nvidia-fabricmanager-local # active (running) +pgrep -af nv-fabricmanager # note: plain pgrep fails, name > 15 chars +tail -30 /usr/local/nvidia/fabricmanager.log +journalctl -u nvidia-fabricmanager-local -n 30 +lspci -k -s # nvidia-nvswitch +lspci -k -s # vfio-pci +``` + +### Guest VM + +Power-cycle the VM after FM starts. The fabric handshake happens during GPU driver init inside the +guest and is not retried, so a VM that was already running will stay broken. + +```bash +nvidia-smi -q | grep -A5 Fabric +``` + +``` +Fabric + State : Completed + Status : Success + CliqueId: 0 +``` + +```bash +python -c "import torch; print(torch.cuda.is_available())" # True +python -c "import torch; print(torch.__version__, torch.version.cuda)" +``` + +--- + +## Part 12 — References + +### NVIDIA — fabric, drivers, concepts + +| Link | What it covers | +|---|---| +| [Fabric Manager User Guide](https://docs.nvidia.com/datacenter/tesla/fabric-manager-user-guide/index.html) | The primary reference. Deployment models, config options, service management, SDK, high-availability modes, troubleshooting | +| [Fabric Manager — full contents](https://docs.nvidia.com/datacenter/tesla/fabric-manager-user-guide/contents.html) | Section-level index; useful for jumping straight to config options or a specific virtualisation model | +| [HGX Software User Guide](https://docs.nvidia.com/datacenter/tesla/hgx-software-guide/index.html) | The complete HGX software stack and install order — driver, NSCQ, FM, DCGM | +| [NVLink & NVSwitch product page](https://www.nvidia.com/en-us/data-center/nvlink/) | Conceptual overview of the interconnect and switch generations | +| [Fabric Manager Client (GitHub)](https://github.com/NVIDIA/Fabric-Manager-Client) | Partition management CLI for Shared NVSwitch mode; also documents `FABRIC_MODE_RESTART` and resiliency | +| [NVIDIA open GPU kernel modules (GitHub)](https://github.com/NVIDIA/open-gpu-kernel-modules) | Source of the open driver — the same code SUSE builds into the KMP used here | +| [NVIDIA CUDA repo for SLES](https://developer.download.nvidia.com/compute/cuda/repos/sles15/x86_64/) | Where `nvidia-fabricmanager` and `libnvidia-nscq` come from | +| [NVIDIA driver repo for SLE](https://download.nvidia.com/suse/sle16/) | Userspace and meta-packages (note: **not** the kernel module) | + +### Harvester / KubeVirt / immutable OS + +| Link | What it covers | +|---|---| +| [Harvester PCI Devices add-on](https://docs.harvesterhci.io/v1.4/advanced/addons/pcidevices/) | Enabling passthrough, `PCIDevice` and `PCIDeviceClaim`, UI workflow | +| [Harvester CloudInit CRD](https://docs.harvesterhci.io/v1.8/advanced/cloudinitcrd/) | Persisting host config on an immutable node via `/oem` | +| [Harvester NVIDIA driver toolkit add-on](https://docs.harvesterhci.io/v1.8/advanced/addons/nvidiadrivertoolkit/) | The vGPU/GRID path — requires a licence, no NVSwitch support | +| [`harvester/pcidevices` (GitHub)](https://github.com/harvester/pcidevices) | Controller internals; how and when devices get bound to `vfio-pci` | +| [KubeVirt host devices / GPU assignment](https://kubevirt.io/user-guide/compute/host-devices/) | `permittedHostDevices`, resource names, VM spec syntax | +| [SUSE Linux Micro documentation](https://documentation.suse.com/sl-micro/6.2/) | Transactional/immutable OS model underlying the Harvester host | + +### VFIO, IOMMU and passthrough background + +| Link | What it covers | +|---|---| +| [Linux kernel VFIO documentation](https://docs.kernel.org/driver-api/vfio.html) | How VFIO groups, containers and device binding actually work | +| [Gentoo Wiki — GPU passthrough](https://wiki.gentoo.org/wiki/GPU_passthrough_with_virt-manager,_QEMU,_and_KVM) | Practical guide; good coverage of large-BAR GPUs and "Above 4G decoding" | +| [ArchWiki — PCI passthrough via OVMF](https://wiki.archlinux.org/title/PCI_passthrough_via_OVMF) | The most thorough community reference on IOMMU groups and ACS | +| [SUSE KMP documentation](https://documentation.suse.com/sles/15-SP6/html/SLES-all/cha-tuning-kernel.html) | Kernel Module Packages and kABI stability within a codestream | + +--- + +## Part 13 — Summary + +| | | +|---|---| +| **Symptom** | CUDA Error 802 in guest; `Fabric State: In Progress` | +| **Root cause** | NVSwitch bridges on the host had no kernel driver bound | +| **Why it was hard** | Immutable read-only root; no package installation possible; no vGPU licence; air-gapped; the real kernel module ships from the distro repo, not NVIDIA's | +| **Solution** | Extract RPMs into the writable persistent partition, `insmod` the module directly, create NVSwitch device nodes manually, run FM from the extracted tree | +| **Result** | `Fabric State: Completed`; `torch.cuda.is_available() == True` | + +### Lessons worth carrying forward + +- Fabric Manager belongs on the **host**, never in a passthrough guest. +- FM alone is useless — it needs the kernel driver and NSCQ, all at the **same version**. +- On SUSE, NVIDIA ships meta-packages; the **distribution** ships the signed kernel module. +- Version selection is a three-way intersection: driver repo × CUDA repo × kernel ABI. +- An immutable root blocks *installation*, not *module loading*. `insmod` takes a path. +- NVSwitch (NVLink fabric) and PCIe switches (IOMMU grouping) are different problems. Don't conflate them. diff --git a/_tabs/about.md b/_tabs/about.md index ddb2bc4..156fe9a 100644 --- a/_tabs/about.md +++ b/_tabs/about.md @@ -4,5 +4,13 @@ icon: fas fa-info-circle order: 4 --- -> Add Markdown syntax content to file `_tabs/about.md`{: .filepath } and it will show up on this page. -{: .prompt-tip } +Hi, I'm Rishabh — I write about platform engineering, Kubernetes, and AI/ML infrastructure. + +This blog, **StackDepth**, is where I dig into the layers. The name is the philosophy — *depth over abstraction*. Expect hands-on notes from real upgrades, migrations, and outages, not just theory. + +You can find me on [GitHub](https://github.com/allexistence) and [LinkedIn](https://www.linkedin.com/in/imrishabh27). + + diff --git a/_tabs/archives.md b/_tabs/archives.md deleted file mode 100644 index c3abc59..0000000 --- a/_tabs/archives.md +++ /dev/null @@ -1,5 +0,0 @@ ---- -layout: archives -icon: fas fa-archive -order: 3 ---- diff --git a/docker-compose.yml b/docker-compose.yml new file mode 100644 index 0000000..c86a16d --- /dev/null +++ b/docker-compose.yml @@ -0,0 +1,10 @@ +name: stackdepth + +services: + site: + build: . + ports: + - "4000:4000" + volumes: + - .:/srv/jekyll + command: bundle exec jekyll serve --host 0.0.0.0 --port 4000