# k3s + rook Homelab _Writeup still a WIP, please pardon the dust._ _Below is mostly braindumps & rough commands for creating/tweaking these services. Formal writeup coming soon!_ # k3s ## installing k3s ``` curl -sfL https://get.k3s.io | INSTALL_K3S_EXEC="server --cluster-init" sh - export NODE_TOKEN=$(cat /var/lib/rancher/k3s/server/node-token) curl -sfL https://get.k3s.io | K3S_TOKEN=$NODE_TOKEN INSTALL_K3S_EXEC="server --server https://192.168.122.87:6443" INSTALL_K3S_VERSION=v1.23.6+k3s1 sh - ``` ## upgrading k3s TODO # rook ## installing rook ``` KUBECONFIG=/etc/rancher/k3s/k3s.yaml helm upgrade --install --create-namespace --namespace rook-ceph rook-ceph rook-release/rook-ceph:1.9.2 -f rook-ceph-values.yaml KUBECONFIG=/etc/rancher/k3s/k3s.yaml helm install --create-namespace --namespace rook-ceph rook-ceph-cluster --set operatorNamespace=rook-ceph rook-release/rook-ceph-cluster:1.9.2 -f rook-ceph-cluster-values.yaml ``` ## upgrading rook TODO ## Finding the physical device for an OSD ceph osd metadata ## tolerations If your setup divides k8s nodes into ceph & non-ceph nodes (using a label, like `storage-node=true`), ensure labels & a toleration are set properly (`storage-node=false`, with a toleration checking for `storage-node`) so non-ceph nodes still run PV plugin Daemonsets. Otherwise, any pod scheduled on a non-ceph node won't be able to mount ceph-backed PVCs. See rook-ceph-cluster-values.yaml->cephClusterSpec->placement for an example. ## CephFS ### EC backing pool EC-backed filesystems require a regular replicated pool as a default. https://lists.ceph.io/hyperkitty/list/ceph-users@ceph.io/thread/QI42CLL3GJ6G7PZEMAD3CXBHA5BNWSYS/ https://tracker.ceph.com/issues/42450 Then setfattr a directory on the filesystem with an EC-backed pool. Any new data written to the folder will go to the EC-backed pool. setfattr -n ceph.dir.layout.pool -v cephfs-erasurecoded /mnt/cephfs/my-erasure-coded-dir https://docs.ceph.com/en/quincy/cephfs/file-layouts/ ### Sharing 1 CephFS instance between multiple PVCs https://github.com/rook/rook/blob/677d3fa47f21b07245e2e4ab6cc964eb44223c48/Documentation/Storage-Configuration/Shared-Filesystem-CephFS/filesystem-storage.md Create CephFilesystem Create SC backed by Filesystem & Pool Ensure the CSI subvolumegroup was created. If not, `ceph fs subvolumegroup create csi` Create PVC without a specified PV: PV will be auto-created _Super important_: Set created PV to ReclaimPolicy: Retain Create a new, better-named PVC ### Resizing a CephFS PVC Grow resources->storage on PV Grow resources->storage on PVC Verify the new limit: `getfattr -n ceph.quota.max_bytes /mnt/volumes/csi/csi-vol-/` ## Crush rules for each pool for i in `ceph osd pool ls`; do echo $i: `ceph osd pool get $i crush_rule`; done On ES backed pools, device class information is in the erasure code profile, not the crush rule. https://docs.ceph.com/en/latest/dev/erasure-coded-pool/ for i in `ceph osd erasure-code-profile ls`; do echo $i: `ceph osd erasure-code-profile get $i`; done ## ObjectStore If hostNetwork is enabled on the cluster, ensure rook-ceph-operator is not running with hostNetwork enable. It doesn't need host network access to orchestrate the cluster, & impedes orchestration of objectstores & associated resources. ## public s3-interface bucket listing w/ HTML This is great for setting up easy public downloads. - Create a user (rook/buckets/user-josh.yaml) - `kubectl -n rook-ceph get secret rook-ceph-object-user-ceph-objectstore-josh -o go-template='{{range $k,$v := .data}}{{printf "%s: " $k}}{{if not $v}}{{$v}}{{else}}{{$v | base64decode}}{{end}}{{"\n"}}{{end}}` - Create bucket (`rook/buckets/bucket.py::create_bucket`) - Set policy (`rook/buckets/bucket.py::set_public_read_policy`) - Upload file ```python from bucket import * conn = connect() conn.upload_file('path/to/s3-bucket-listing/index.html', 'public', 'index.html', ExtraArgs={'ContentType': 'text/html'}) ``` # nvidia driver (on debian) ``` curl -s -L https://nvidia.github.io/nvidia-container-runtime/gpgkey | sudo apt-key add - distribution=$(. /etc/os-release;echo $ID$VERSION_ID) curl -s -L https://nvidia.github.io/nvidia-container-runtime/$distribution/nvidia-container-runtime.list | sudo tee /etc/apt/sources.list.d/nvidia-container-runtime.list wget https://developer.download.nvidia.com/compute/cuda/11.6.2/local_installers/cuda-repo-debian11-11-6-local_11.6.2-510.47.03-1_amd64.deb sudo dpkg -i cuda-repo-debian11-11-6-local_11.6.2-510.47.03-1_amd64.deb sudo apt-key add /var/cuda-repo-debian11-11-6-local/7fa2af80.pub sudo apt-get update ``` ## install kernel headers ``` sudo apt install cuda nvidia-container-runtime nvidia-kernel-dkms sudo apt install --reinstall nvidia-kernel-dkms ``` ## verify dkms is actually running ``` sudo vi /etc/modprobe.d/blacklist-nvidia-nouveau.conf blacklist nouveau options nouveau modeset=0 sudo update-initramfs -u ``` ## configure containerd to use nvidia by default Copy https://github.com/k3s-io/k3s/blob/v1.24.2%2Bk3s2/pkg/agent/templates/templates_linux.go into /var/lib/rancher/k3s/agent/etc/containerd/config.toml.tmpl (substitute your k3s version) Edit the file: ``` <... snip> conf_dir = "{{ .NodeConfig.AgentConfig.CNIConfDir }}" {{end}} [plugins.cri.containerd.runtimes.runc] runtime_type = "io.containerd.runc.v2" [plugins.cri.containerd.runtimes.runc.options] BinaryName = "/usr/bin/nvidia-container-runtime" {{ if .PrivateRegistryConfig }} <... snip> ``` & then `systemctl restart k3s` Label your GPU-capable nodes: `kubectl label nodes gpu-node=true` & then install the nvidia device plugin: ``` helm repo add nvdp https://nvidia.github.io/k8s-device-plugin helm repo update KUBECONFIG=/etc/rancher/k3s/k3s.yaml helm upgrade -i nvdp nvdp/nvidia-device-plugin --version=0.12.2 --namespace nvidia-device-plugin --create-namespace --set-string nodeSelector.gpu-node=true ``` Ensure the pods on the namespace are Running. Test GPU passthrough by applying examples/cuda-pod.yaml, then exec-ing into it & running `nvidia-smi`. ## Sharing GPU https://github.com/NVIDIA/k8s-device-plugin#shared-access-to-gpus-with-cuda-time-slicing ```yaml version: v1 sharing: timeSlicing: renameByDefault: false failRequestsGreaterThanOne: false resources: - name: nvidia.com/gpu replicas: 5 ``` ``` $ helm upgrade -i nvdp nvdp/nvidia-device-plugin ... --set-file config.map.config=nvidia-device-plugin-config.yaml ``` # ceph client for cephfs volumes ## New method https://docs.ceph.com/en/latest/man/8/mount.ceph/ ``` sudo mount -t ceph user@.=/ /mnt/ceph -o secret=,x-systemd.requires=ceph.target,x-systemd.mount-timeout=5min,_netdev,mon_addr=192.168.1.1 ``` ## Older method (stopped working for me around Pacific) ``` sudo vi /etc/fstab 192.168.1.1,192.168.1.2:/ /ceph ceph name=admin,secret=,x-systemd.mount-timeout=5min,_netdev,mds_namespace=data ``` # disable mitigations https://unix.stackexchange.com/questions/554908/disable-spectre-and-meltdown-mitigations # Monitoring https://rpi4cluster.com/monitoring/monitor-intro/, + what's in the `monitoring` folder. Tried https://github.com/prometheus-operator/kube-prometheus. The only way to persist dashboards is to add them to Jsonnet & apply the generated configmap. I'm not ready for that kind of IaC commitment in a homelab. # Exposing internal services ``` kubectl expose svc/some-service --name=some-service-external --port 1234 --target-port 1234 --type LoadBalancer ``` Service will then be available on port 1234 of any k8s node. # libvirtd ... # Still to do - deluge - gogs ssh ingress (can't go through cloudflare without cloudflared on the client) - Something better than `expose` for accessing internal services - replicated_ssd crush rule never resolves (or didn't on `data-metadata`)