### Example output of V1 install preflight

Source: https://longhorn.io/docs/1.12.1/deploy/install

Example output from running the V1 install preflight command, showing the installation steps and completion message.

```text
INFO[2025-03-11T08:17:57+08:00] Initializing preflight installer
INFO[2025-03-11T08:17:57+08:00] Cleaning up preflight installer
INFO[2025-03-11T08:17:57+08:00] Running preflight installer
INFO[2025-03-11T08:17:57+08:00] Installing dependencies with package manager
INFO[2025-03-11T08:18:28+08:00] Installed dependencies with package manager
INFO[2025-03-11T08:18:28+08:00] Cleaning up preflight installer
INFO[2025-03-11T08:18:28+08:00] Completed preflight installer. Use 'longhornctl check preflight' to check the result.

```

--------------------------------

### Successful Longhorn Installation Pod List

Source: https://longhorn.io/docs/1.12.1/deploy/install/install-with-fleet

Example output of a successful Longhorn installation, showing all expected pods in Running status. Use this to verify the installation completed successfully.

```text
NAME                                                READY   STATUS    RESTARTS   AGE
longhorn-ui-b7c844b49-w25g5                         1/1     Running   0          2m41s
longhorn-manager-pzgsp                              1/1     Running   0          2m41s
longhorn-driver-deployer-6bd59c9f76-lqczw           1/1     Running   0          2m41s
longhorn-csi-plugin-mbwqz                           2/2     Running   0          100s
csi-snapshotter-588457fcdf-22bqp                    1/1     Running   0          100s
csi-snapshotter-588457fcdf-2wd6g                    1/1     Running   0          100s
csi-provisioner-869bdc4b79-mzrwf                    1/1     Running   0          101s
csi-provisioner-869bdc4b79-klgfm                    1/1     Running   0          101s
csi-resizer-6d8cf5f99f-fd2ck                        1/1     Running   0          101s
csi-provisioner-869bdc4b79-j46rx                    1/1     Running   0          101s
csi-snapshotter-588457fcdf-bvjdt                    1/1     Running   0          100s
csi-resizer-6d8cf5f99f-68cw7                        1/1     Running   0          101s
csi-attacher-7bf4b7f996-df8v6                       1/1     Running   0          101s
csi-attacher-7bf4b7f996-g9cwc                       1/1     Running   0          101s
csi-attacher-7bf4b7f996-8l9sw                       1/1     Running   0          101s
csi-resizer-6d8cf5f99f-smdjw                        1/1     Running   0          101s
instance-manager-b34d5db1fe1e2d52bcfb308be3166cfc   1/1     Running   0          114s
engine-image-ei-df38d2e5-cv6nc                      1/1     Running   0          114s
```

--------------------------------

### Install prerequisites for V2 Data Engine with --enable-spdk

Source: https://longhorn.io/docs/1.12.1/deploy/install

Installs additional V2 prerequisites using the install preflight command with --enable-spdk.

```bash
longhornctl --kubeconfig ~/.kube/config --image longhornio/longhorn-cli:v1.12.1 install preflight --enable-spdk

```

--------------------------------

### Show created resources with kubectl get

Source: https://longhorn.io/docs/1.12.1/deploy/install/install-with-helm-controller

Show the created resources after applying the HelmChart: the installation job, the pod that runs the Helm install, and the HelmChart resource itself. The pod shows Completed status, indicating the installation job finished successfully.

```bash
$ kubectl get jobs
NAME                            COMPLETIONS   DURATION   AGE
helm-install-longhorn-install   0/1           8s         8s

$ kubectl get pods
NAME                                  READY   STATUS      RESTARTS   AGE
helm-install-longhorn-install-lngm8   0/1     Completed   0          25s

$ kubectl get helmcharts
NAME               JOB                     CHART      TARGETNAMESPACE   VERSION   REPO                         HELMVERSION   BOOTSTRAP
longhorn-install   helm-install-longhorn   longhorn   longhorn-system   v1.12.1    https://charts.longhorn.io

```

--------------------------------

### Example output: IOMMU enabled

Source: https://longhorn.io/docs/1.12.1/advanced-resources/v2-data-engine/interrupt-mode

Example output when IOMMU is enabled, showing device paths under the iommu_groups directories.

```text
/sys/kernel/iommu_groups/0/devices/0000:e6:0b.1
/sys/kernel/iommu_groups/1/devices/0000:34:0a.6
/sys/kernel/iommu_groups/2/devices/0000:a0:00.0
```

--------------------------------

### Install cryptsetup on SUSE/OpenSUSE

Source: https://longhorn.io/docs/1.12.1/deploy/install

Use this command to install cryptsetup for LUKS2 disk encryption support on SUSE/OpenSUSE.

```bash
zypper install cryptsetup

```

--------------------------------

### Install NFSv4 client on SUSE/OpenSUSE

Source: https://longhorn.io/docs/1.12.1/deploy/install

Use this command to install the NFSv4 client utilities on SUSE/OpenSUSE.

```bash
zypper install nfs-client

```

--------------------------------

### Install open-iscsi on SUSE and openSUSE

Source: https://longhorn.io/docs/1.12.1/deploy/install

Use these commands to install and start the open-iscsi service on SUSE and openSUSE systems. The iscsid daemon must be running for Longhorn to provide persistent volumes.

```bash
zypper install open-iscsi
systemctl enable iscsid
systemctl start iscsid

```

--------------------------------

### Install prerequisites for V1 Data Engine

Source: https://longhorn.io/docs/1.12.1/deploy/install

Installs base prerequisites for the default V1 installation path using the longhornctl install preflight command.

```bash
longhornctl --kubeconfig ~/.kube/config --image longhornio/longhorn-cli:v1.12.1 install preflight

```

--------------------------------

### Install longhornctl binary

Source: https://longhorn.io/docs/1.12.1/advanced-resources/longhornctl/install-longhornctl

Installs the downloaded longhornctl binary to /usr/local/bin using sudo install.

```bash
sudo install longhornctl-linux-${ARCH} /usr/local/bin/longhornctl
```

--------------------------------

### Install device mapper on Debian/Ubuntu

Source: https://longhorn.io/docs/1.12.1/deploy/install

Use this command to install the device mapper userspace tool (dmsetup) on Debian and Ubuntu.

```bash
apt-get install dmsetup

```

--------------------------------

### Example output of V1 preflight check

Source: https://longhorn.io/docs/1.12.1/deploy/install

Example output from running the V1 preflight check, showing info and warnings for worker nodes.

```text
INFO[2024-01-01T00:00:01Z] Initializing preflight checker
INFO[2024-01-01T00:00:01Z] Cleaning up preflight checker
INFO[2024-01-01T00:00:01Z] Running preflight checker
INFO[2024-01-01T00:00:02Z] Retrieved preflight checker result:
worker1:
  info:
  - Service iscsid is running
  - NFS4 is supported
  - Package nfs-common is installed
  - Package open-iscsi is installed
  warn:
  - multipathd.service is running. Please refer to https://longhorn.io/kb/troubleshooting-volume-with-multipath/ for more information.
worker2:
  info:
  - Service iscsid is running
  - NFS4 is supported
  - Package nfs-common is not installed
  - Package open-iscsi is installed

```

--------------------------------

### Install device mapper on SUSE/OpenSUSE

Source: https://longhorn.io/docs/1.12.1/deploy/install

Use this command to install the device mapper userspace tool (device-mapper) on SUSE/OpenSUSE.

```bash
zypper install device-mapper

```

--------------------------------

### Docker command example with actual values

Source: https://longhorn.io/docs/1.12.1/advanced-resources/data-recovery/export-from-replica

Example Docker command using the values from the previous steps: data path /var/lib/longhorn/replicas/pvc-06b4a8a8-b51d-42c6-a8cc-d8c8d6bc65bc-d890efb2, volume name pvc-06b4a8a8-b51d-42c6-a8cc-d8c8d6bc65bc, and size 1073741824.

```bash
docker run -v /dev:/host/dev -v /proc:/host/proc -v /var/lib/longhorn/replicas/pvc-06b4a8a8-b51d-42c6-a8cc-d8c8d6bc65bc-d890efb2:/volume --privileged longhornio/longhorn-engine:v1.12.1 launch-simple-longhorn pvc-06b4a8a8-b51d-42c6-a8cc-d8c8d6bc65bc 1073741824

```

--------------------------------

### Install open-iscsi on Debian and Ubuntu

Source: https://longhorn.io/docs/1.12.1/deploy/install

Use this command to install open-iscsi on Debian and Ubuntu systems. The iscsid service is typically started automatically after installation.

```bash
apt-get install open-iscsi

```

--------------------------------

### Expected pod list after Longhorn installation

Source: https://longhorn.io/docs/1.12.1/deploy/install/install-with-helm

Expected output of `kubectl -n longhorn-system get pod` after a successful Longhorn installation, showing all pods in Running state.

```text
NAME                                                READY   STATUS    RESTARTS   AGE
longhorn-ui-b7c844b49-w25g5                         1/1     Running   0          2m41s
longhorn-manager-pzgsp                              1/1     Running   0          2m41s
longhorn-driver-deployer-6bd59c9f76-lqczw           1/1     Running   0          2m41s
longhorn-csi-plugin-mbwqz                           2/2     Running   0          100s
csi-snapshotter-588457fcdf-22bqp                    1/1     Running   0          100s
csi-snapshotter-588457fcdf-2wd6g                    1/1     Running   0          100s
csi-provisioner-869bdc4b79-mzrwf                    1/1     Running   0          101s
csi-provisioner-869bdc4b79-klgfm                    1/1     Running   0          101s
csi-resizer-6d8cf5f99f-fd2ck                        1/1     Running   0          101s
csi-provisioner-869bdc4b79-j46rx                    1/1     Running   0          101s
csi-snapshotter-588457fcdf-bvjdt                    1/1     Running   0          100s
csi-resizer-6d8cf5f99f-68cw7                        1/1     Running   0          101s
csi-attacher-7bf4b7f996-df8v6                       1/1     Running   0          101s
csi-attacher-7bf4b7f996-g9cwc                       1/1     Running   0          101s
csi-attacher-7bf4b7f996-8l9sw                       1/1     Running   0          101s
csi-resizer-6d8cf5f99f-smdjw                        1/1     Running   0          101s
instance-manager-b34d5db1fe1e2d52bcfb308be3166cfc   1/1     Running   0          114s
engine-image-ei-df38d2e5-cv6nc                      1/1     Running   0          114s

```

--------------------------------

### Example: Trigger checksum for all volumes

Source: https://longhorn.io/docs/1.12.1/advanced-resources/data-integrity/on-demand-snapshot-data-integrity

Example command to trigger on-demand snapshot checksum for all volumes using the longhornctl binary.

```bash
./longhornctl-linux-amd64 checksum volume --all=true

```

--------------------------------

### Helm install with --set flag

Source: https://longhorn.io/docs/1.12.1/advanced-resources/deploy/customizing-default-settings

Use this command to install Longhorn with custom default settings by passing them directly via the --set flag. The example sets the taintToleration setting. Requires Helm 3.

```bash
helm install longhorn longhorn/longhorn \
  --namespace longhorn-system \
  --create-namespace \
  --set defaultSettings.taintToleration="key1=value1:NoSchedule; key2:NoExecute"

```

--------------------------------

### Install open-iscsi on RHEL, CentOS, and EKS

Source: https://longhorn.io/docs/1.12.1/deploy/install

Use these commands to install and configure open-iscsi on RHEL, CentOS, and EKS (with AmazonLinux2 image). The initiator name is set automatically, and the iscsid service is enabled and started.

```bash
yum --setopt=tsflags=noscripts install iscsi-initiator-utils
echo "InitiatorName=$(/sbin/iscsi-iname)" > /etc/iscsi/initiatorname.iscsi
systemctl enable iscsid
systemctl start iscsid

```

--------------------------------

### Create Argo CD namespace and install core components

Source: https://longhorn.io/docs/1.12.1/deploy/install/install-with-argocd

Run these commands to create the 'argocd' namespace and apply the Argo CD core installation manifest. Wait for the Argo CD components to be deployed before proceeding.

```bash
kubectl create namespace argocd
kubectl apply -n argocd -f https://raw.githubusercontent.com/argoproj/argo-cd/stable/manifests/core-install.yaml

```

--------------------------------

### Monitor Longhorn Installation

Source: https://longhorn.io/docs/1.12.1/advanced-resources/os-distro-specific/okd-support

Watch the pods in the longhorn-system namespace to track the installation progress.

```bash
  oc get pods \
  --namespace longhorn-system \
  --watch
```

--------------------------------

### Install cryptsetup on Debian/Ubuntu

Source: https://longhorn.io/docs/1.12.1/deploy/install

Use this command to install cryptsetup for LUKS2 disk encryption support on Debian and Ubuntu.

```bash
apt-get install cryptsetup

```

--------------------------------

### Install Longhorn with Helm

Source: https://longhorn.io/docs/1.12.1/deploy/install/airgap

Installs Longhorn using the Helm chart into the longhorn-system namespace, creating the namespace if it does not exist.

```bash
helm install longhorn ./chart --namespace longhorn-system --create-namespace
```

--------------------------------

### Install Longhorn with HTTPRoute enabled

Source: https://longhorn.io/docs/1.12.1/deploy/accessing-the-ui/longhorn-httproute

Installs Longhorn with HTTPRoute generation enabled, referencing a Gateway named my-gateway in the default namespace and the hostname longhorn.example.com.

```bash
helm install longhorn longhorn/longhorn \
  --namespace longhorn-system \
  --create-namespace \
  --set "httproute.enabled=true" \
  --set "httproute.parentRefs[0].name=my-gateway" \
  --set "httproute.parentRefs[0].namespace=default" \
  --set "httproute.hostnames[0]=longhorn.example.com"

```

--------------------------------

### Install Fleet using Helm

Source: https://longhorn.io/docs/1.12.1/deploy/install/install-with-fleet

Adds the Fleet Helm repository and installs the fleet-crd and fleet charts in the cattle-fleet-system namespace.

```bash
helm repo add fleet https://rancher.github.io/fleet-helm-charts/
helm -n cattle-fleet-system install --create-namespace --wait fleet-crd fleet/fleet-crd
helm -n cattle-fleet-system install --create-namespace --wait fleet fleet/fleet

```

--------------------------------

### Backup configuration file content example

Source: https://longhorn.io/docs/1.12.1/advanced-resources/data-recovery/recover-without-system

Example content of a backup.cfg file showing the backup name, volume name, and snapshot name. Used to retrieve the backup name and volume name for the restore command.

```json
{"Name":"backup-72bcbdad913546cf","VolumeName":"volume_1","SnapshotName":"79758033-a670-4724-906f-41921f53c475"}
```

--------------------------------

### Example Output of ls -al /sys/block/ for NVMe Disks

Source: https://longhorn.io/docs/1.12.1/nodes-and-volumes/nodes/multidisk

Example output showing symlinks for loop0, nvme0n1, and nvme1n1. The BDF of /dev/nvme1n1 is 0000:05:00.0.

```bash
lrwxrwxrwx  1 root root 0 Jul 30 12:20 loop0 -> ../devices/virtual/block/loop0
lrwxrwxrwx  1 root root 0 Jul 30 12:20 nvme0n1 -> ../devices/pci0000:00/0000:00:01.2/0000:02:00.0/nvme/nvme0/nvme0n1
lrwxrwxrwx  1 root root 0 Jul 30 12:20 nvme1n1 -> ../devices/pci0000:00/0000:00:01.2/0000:05:00.0/nvme/nvme1/nvme1n1

```

--------------------------------

### Example values.yaml snippet

Source: https://longhorn.io/docs/1.12.1/advanced-resources/deploy/customizing-default-settings

Shows an example of modified default settings in the values.yaml file. Settings with a leading '#' or absent use the default value in Longhorn or previously configured custom values.

```yaml
defaultSettings:
  backupTarget: s3://backupbucket@us-east-1/backupstore
  backupTargetCredentialSecret: minio-secret
  createDefaultDiskLabeledNodes: true
  defaultDataPath: /var/lib/longhorn-example/
  replicaSoftAntiAffinity: false
  storageOverProvisioningPercentage: 600
  storageMinimalAvailablePercentage: 15
  upgradeChecker: false
  defaultReplicaCount: 2
  defaultDataLocality: disabled
  defaultLonghornStaticStorageClass: longhorn-static-example
  backupstorePollInterval: 500
  taintToleration: key1=value1:NoSchedule; key2:NoExecute
  systemManagedComponentsNodeSelector: "label-key1:label-value1"
  priorityClass: high-priority
  autoSalvage: false
  disableSchedulingOnCordonedNode: false
  replicaZoneSoftAntiAffinity: false
  replicaDiskSoftAntiAffinity: false
  volumeAttachmentRecoveryPolicy: never
  nodeDownPodDeletionPolicy: do-nothing
  guaranteedInstanceManagerCpu: 15
  orphanResourceAutoDeletion: ""
  orphanResourceAutoDeletionGracePeriod: 300

```

--------------------------------

### Example Output of ls -al /sys/block/ for VirtIO Disks

Source: https://longhorn.io/docs/1.12.1/nodes-and-volumes/nodes/multidisk

Example output showing symlinks for vda and vdb. The BDF of /dev/vdb is 0000:07:00.0.

```bash
lrwxrwxrwx  1 root root 0 Feb 22 14:04 vda -> ../devices/pci0000:00/0000:00:02.3/0000:04:00.0/virtio2/block/vda
lrwxrwxrwx  1 root root 0 Feb 22 14:24 vdb -> ../devices/pci0000:00/0000:00:02.6/0000:07:00.0/virtio5/block/vdb

```

--------------------------------

### Check prerequisites for V1 Data Engine

Source: https://longhorn.io/docs/1.12.1/deploy/install

Runs the base preflight check for the default V1 installation path.

```bash
./longhornctl check preflight

```

--------------------------------

### Expected Longhorn installation pod status output

Source: https://longhorn.io/docs/1.12.1/deploy/install/install-with-helm-controller

Shows the expected output of the Longhorn installation command, listing all running pods with their READY, STATUS, RESTARTS, and AGE columns. Use this to verify that all Longhorn components are running correctly after installation.

```plaintext
NAME                                                READY   STATUS    RESTARTS      AGE
csi-attacher-85c7684cfd-67kqc                       1/1     Running   0             29m
csi-attacher-85c7684cfd-jbddj                       1/1     Running   0             29m
csi-attacher-85c7684cfd-t85bw                       1/1     Running   0             29m
csi-provisioner-68cdb8b96-46d9q                     1/1     Running   0             29m
csi-provisioner-68cdb8b96-dgf5f                     1/1     Running   0             29m
csi-provisioner-68cdb8b96-mh8q7                     1/1     Running   0             29m
csi-resizer-86dd765b9-d27cs                         1/1     Running   0             29m
csi-resizer-86dd765b9-scqxm                         1/1     Running   0             29m
csi-resizer-86dd765b9-zpcv7                         1/1     Running   0             29m
csi-snapshotter-65b46b8749-dtvh2                    1/1     Running   0             29m
csi-snapshotter-65b46b8749-g67fn                    1/1     Running   0             29m
csi-snapshotter-65b46b8749-nfgzm                    1/1     Running   0             29m
engine-image-ei-221c9c21-gd5d6                      1/1     Running   0             29m
engine-image-ei-221c9c21-v6clp                      1/1     Running   0             29m
engine-image-ei-221c9c21-zzdrt                      1/1     Running   0             29m
instance-manager-77d11dda6091967f9b30011c9876341b   1/1     Running   0             29m
instance-manager-870c250b69a4fe01382ed46156d33f47   1/1     Running   0             29m
instance-manager-a4099c5ce28b423c3cc2667906f4b0b4   1/1     Running   0             29m
longhorn-csi-plugin-jfbh5                           3/3     Running   0             29m
longhorn-csi-plugin-w768w                           3/3     Running   0             29m
longhorn-csi-plugin-xcghm                           3/3     Running   0             29m
longhorn-driver-deployer-586bc86bf9-bkwk6           1/1     Running   0             30m
longhorn-manager-c4xtv                              1/1     Running   1 (30m ago)   30m
longhorn-manager-kgqts                              1/1     Running   0             30m
longhorn-manager-n8xdr                              1/1     Running   0             30m
longhorn-ui-69667f9678-2lvxn                        1/1     Running   0             30m
longhorn-ui-69667f9678-2xmc9                        1/1     Running   0             30m

```

--------------------------------

### Helm install with values.yaml

Source: https://longhorn.io/docs/1.12.1/advanced-resources/deploy/customizing-default-settings

Installs Longhorn using a modified values.yaml file by passing it with the --values flag.

```bash
helm install longhorn longhorn/longhorn \
  --namespace longhorn-system \
  --create-namespace \
  --values values.yaml

```

--------------------------------

### Install NFSv4 client on Debian/Ubuntu

Source: https://longhorn.io/docs/1.12.1/deploy/install

Use this command to install the NFSv4 client utilities on Debian and Ubuntu systems.

```bash
apt-get install nfs-common

```

--------------------------------

### Helm Controller spec.set example

Source: https://longhorn.io/docs/1.12.1/advanced-resources/deploy/customizing-default-settings

Shows how to set default settings in the HelmChart YAML file by adding lines to spec.set. The example sets priorityClass, replicaAutoBalance, storageOverProvisioningPercentage, and defaultClassReplicaCount.

```yaml
spec:
  ...
  set:
    defaultSettings.priorityClass: system-node-critical
    defaultSettings.replicaAutoBalance: least-effort
    defaultSettings.storageOverProvisioningPercentage: "200"
    persistence.defaultClassReplicaCount: "2"

```

--------------------------------

### Replica directory path example

Source: https://longhorn.io/docs/1.12.1/advanced-resources/data-recovery/corrupted-replica

Example path where a Longhorn replica's data is stored on a node. Used to locate the replica directory before running checksums.

```bash
/var/lib/longhorn/replicas/pvc-06b4a8a8-b51d-42c6-a8cc-d8c8d6bc65bc-d890efb2
```

--------------------------------

### Install Longhorn with Helm on OpenShift

Source: https://longhorn.io/docs/1.12.1/advanced-resources/os-distro-specific/okd-support

Use the helm install command with specific OpenShift-related flags to enable OAuth proxy support.

```bash
  helm install longhorn longhorn/longhorn \
    --namespace longhorn-system \
    --create-namespace \
    --set openshift.enabled=true \
    --set image.openshift.oauthProxy.registry=quay.io \
    --set image.openshift.oauthProxy.repository=openshift/origin-oauth-proxy \
    --set image.openshift.oauthProxy.tag=4.18
```

--------------------------------

### Install cryptsetup on RHEL/CentOS/Rocky/EKS

Source: https://longhorn.io/docs/1.12.1/deploy/install

Use this command to install cryptsetup for LUKS2 disk encryption support on RHEL, CentOS, Rocky Linux, and EKS with AmazonLinux2 image.

```bash
yum install cryptsetup

```

--------------------------------

### Install Longhorn with Helm

Source: https://longhorn.io/docs/1.12.1/deploy/install/install-with-helm

Commands to add the Longhorn Helm repository, update the repository, install Longhorn in the longhorn-system namespace, and verify the deployment by listing pods.

```bash
helm repo add longhorn https://charts.longhorn.io

```

```bash
helm repo update

```

```bash
helm install longhorn longhorn/longhorn --namespace longhorn-system --create-namespace --version 1.12.1

```

```bash
kubectl -n longhorn-system get pod

```

--------------------------------

### Get Kubelet Logs with Docker

Source: https://longhorn.io/docs/1.12.1/troubleshoot/troubleshooting

Get kubelet logs when kubelet runs as a container (e.g., in RKE). Useful for troubleshooting the FlexVolume driver.

```bash
docker logs kubelet

```

--------------------------------

### Example logs from longhorn-manager pods after restore

Source: https://longhorn.io/docs/1.12.1/advanced-resources/system-backup-restore/restore-to-a-new-cluster-using-velero

These are example warning logs that appear in longhorn-manager pods when old instance manager pods are present. They indicate that the pods cannot be found and are harmless but cause endless logs.

```log
[longhorn-manager-q6n7x] time="2021-12-20T10:42:49Z" level=warning msg="Can't find instance manager for pod instance-manager-r-1f19ecb0, may be deleted"
[longhorn-manager-q6n7x] time="2021-12-20T10:42:49Z" level=warning msg="Can't find instance manager for pod instance-manager-e-6c3be222, may be deleted"
[longhorn-manager-ldlvw] time="2021-12-20T10:42:55Z" level=warning msg="Can't find instance manager for pod instance-manager-e-bbf80f76, may be deleted"
[longhorn-manager-ldlvw] time="2021-12-20T10:42:55Z" level=warning msg="Can't find instance manager for pod instance-manager-r-3818fdca, may be deleted"
```

--------------------------------

### Start iSCSI daemon for current session

Source: https://longhorn.io/docs/1.12.1/advanced-resources/os-distro-specific/csi-on-rke-and-coreos

Starts the iSCSI daemon immediately for the current session without enabling it at boot. Requires sudo access.

```bash
sudo su
systemctl start iscsid
```

--------------------------------

### Example: Modified longhorn-ui Deployment for private registry

Source: https://longhorn.io/docs/1.12.1/deploy/install/airgap

Example of the longhorn-ui Deployment manifest with the image modified to point to your private registry and the imagePullSecrets name added. Replace <REGISTRY_URL>, <LONGHORN_UI_IMAGE_TAG>, and <SECRET_NAME> with your values.

```yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: longhorn-ui
  name: longhorn-ui
  namespace: longhorn-system
spec:
  replicas: 1
  selector:
    matchLabels:
      app: longhorn-ui
  template:
    metadata:
      labels:
        app: longhorn-ui
    spec:
      containers:
      - name: longhorn-ui
        image: <REGISTRY_URL>/longhorn-ui:<LONGHORN_UI_IMAGE_TAG>   ## Add image name and tag here
        ports:
        - containerPort: 8000
        env:
          - name: LONGHORN_MANAGER_IP
            value: "http://longhorn-backend:9500"
      imagePullSecrets:
      - name: <SECRET_NAME>
      serviceAccountName: longhorn-service-account

```

--------------------------------

### Pre-upgrade job failure event example

Source: https://longhorn.io/docs/1.12.1/deploy/upgrade/longhorn-manager

Example event output from the pre-upgrade job when upgrading from an unsupported version. It shows the failure reason, e.g., upgrading from v1.6.2 to v1.8.0 for minor version is not supported.

```bash
2m33s               Normal    Created                 Pod/longhorn-pre-upgrade-v5tqq    Created container longhorn-pre-upgrade
2m33s               Warning   FailedUpgradePreCheck   /longhorn-pre-upgrade             failed to upgrade since upgrading from v1.6.2 to v1.8.0 for minor version is not supported

```

--------------------------------

### Install Longhorn with kubectl apply

Source: https://longhorn.io/docs/1.12.1/deploy/install/install-with-kubectl

Applies the Longhorn v1.12.1 manifest to install Longhorn on a Kubernetes cluster. Run this command first to start the installation.

```bash
kubectl apply -f https://raw.githubusercontent.com/longhorn/longhorn/v1.12.1/deploy/longhorn.yaml

```

--------------------------------

### Set up SMB/CIFS Backupstore

Source: https://longhorn.io/docs/1.12.1/snapshots-and-backups/backup-and-restore/set-backup-target

Create a credential secret for SMB/CIFS backupstore and deploy it. The script generates a secret YAML with base64-encoded credentials and applies it. Then set environment variables, generate a Kustomize overlay, and deploy the credentials and service.

```bash
#!/bin/bash

USERNAME=${Username of SMB/CIFS Server}
PASSWORD=${Password of SMB/CIFS Server}

CIFS_USERNAME=`echo -n ${USERNAME} | base64`
CIFS_PASSWORD=`echo -n ${PASSWORD} | base64`

cat <<EOF >>cifs_secret.yml
apiVersion: v1
kind: Secret
metadata:
  name: cifs-secret
  namespace: longhorn-system
type: Opaque
data:
  CIFS_USERNAME: ${CIFS_USERNAME}
  CIFS_PASSWORD: ${CIFS_PASSWORD}
EOF

kubectl apply -f cifs_secret.yml

```

```bash
export CIFS_USERNAME="example-cifs-username"
export CIFS_PASSWORD="example-cifs-password"

```

```bash
./scripts/generate-backupstore-credentials.sh cifs

```

```bash
kubectl apply -k deploy/backupstores/overlays/generated-credentials/cifs

```

--------------------------------

### Default disks configuration annotation example

Source: https://longhorn.io/docs/1.12.1/nodes-and-volumes/nodes/default-disk-and-node-config

Example of a disk configuration with two disks. The first disk uses the default path, the second has a custom name, path, scheduling disabled, storage reserved, and tags.

```plaintext
node.longhorn.io/default-disks-config: 
'[
    { 
        "path":"/mnt/disk1",
        "allowScheduling":true
    },
    {   
        "name":"fast-ssd-disk", 
        "path":"/mnt/disk2",
        "allowScheduling":false,
        "storageReserved":10485760,
        "tags":[
            "ssd",
            "fast"
        ]
    }
]'
```

--------------------------------

### Find kubelet root-dir with ps aux

Source: https://longhorn.io/docs/1.12.1/advanced-resources/os-distro-specific/csi-on-rke-and-coreos

Shows how to locate the kubelet root-dir by running ps aux and grepping for kubelet. The example output displays the --root-dir argument.

```bash
$ ps aux | grep kubelet
root      3755  4.4  2.9 744404 120020 ?       Ssl  00:45   0:02 kubelet --root-dir=/opt/rke/var/lib/kubelet --volume-plugin-dir=/var/lib/kubelet/volumeplugins
```

--------------------------------

### Longhorn Python client usage for volume, node, and setting operations

Source: https://longhorn.io/docs/1.12.1/references/longhorn-client-python

Import the longhorn.py client and create a client from the endpoint. The script demonstrates volume operations (list, get by ID, attach, detach, snapshot create, snapshot backup, update replica count), node operations (list, get by ID, enable/disable scheduling), and setting operations (list, get by ID, update). The endpoint URL depends on whether the script runs inside the cluster or on a local machine with port-forwarding.

```python
import longhorn

# If automation/scripting tool is inside the same cluster in which Longhorn is installed
longhorn_url = 'http://longhorn-frontend.longhorn-system/v1'
# If forwarding `longhorn-frontend` service to localhost
longhorn_url = 'http://localhost:8080/v1'

client = longhorn.Client(url=longhorn_url)

# Volume operations
# List all volumes
volumes = client.list_volume()
# Get volume by NAME/ID
testvol1 = client.by_id_volume(id="testvol1")
# Attach TESTVOL1
testvol1 = testvol1.attach(hostId="worker-1")
# Detach TESTVOL1
testvol1.detach()
# Create a snapshot of TESTVOL1 with NAME
snapshot1 = testvol1.snapshotCreate(name="snapshot1")
# Create a backup from a snapshot NAME
testvol1.snapshotBackup(name=snapshot1.name)
# Update the number of replicas of TESTVOL1
testvol1.updateReplicaCount(replicaCount=2)
# Find more examples in Longhorn integration tests https://github.com/longhorn/longhorn-tests/tree/master/manager/integration/tests

# Node operations
# List all nodes
nodes = client.list_node()
# Get node by NAME/ID
node1 = client.by_id_node(id="worker-1")
# Disable scheduling for NODE1
client.update(node1, allowScheduling=False)
# Enable scheduling for NODE1
client.update(node1, allowScheduling=True)
# Find more examples in Longhorn integration tests https://github.com/longhorn/longhorn-tests/tree/master/manager/integration/tests

# Setting operations
# List all settings
settings = client.list_setting()
# Get setting by NAME/ID
backupTargetsetting = client.by_id_setting(id="backup-target")
# Update a setting
backupTargetsetting = client.update(backupTargetsetting, value="s3://backupbucket@us-east-1/")
# Find more examples in Longhorn integration tests https://github.com/longhorn/longhorn-tests/tree/master/manager/integration/tests

```

--------------------------------

### Create HelmChart YAML for Longhorn installation

Source: https://longhorn.io/docs/1.12.1/deploy/install/install-with-helm-controller

Create a HelmChart custom resource to install Longhorn via the Helm controller in RKE2 or K3s. Set spec.failurePolicy to "abort" to avoid automatic uninstall on failure; the default "reinstall" would uninstall Longhorn. The chart is pulled from the Longhorn Helm repository.

```yaml
apiVersion: helm.cattle.io/v1
kind: HelmChart
metadata:
  annotations:
    helmcharts.cattle.io/managed-by: helm-controller
  finalizers:
  - wrangler.cattle.io/on-helm-chart-remove
  generation: 1
  name: longhorn-install
  namespace: default
spec:
  version: v1.12.1
  chart: longhorn
  repo: https://charts.longhorn.io
  failurePolicy: abort
  targetNamespace: longhorn-system
  createNamespace: true

```

--------------------------------

### VirtIO Disk Configuration Example

Source: https://longhorn.io/docs/1.12.1/nodes-and-volumes/nodes/multidisk

Example of adding a VirtIO disk to spec.disks using diskDriver: auto and path set to the BDF (0000:07:00.0). Using /dev/vdb instead would cause Longhorn to treat it as an aio disk.

```yaml
virtio-disk:
  allowScheduling: true
  diskType: block
  diskDriver: auto
  evictionRequested: false
  path: 0000:07:00.0
  storageReserved: 0
  tags: []

```

--------------------------------

### System Managed CSI Components Resource Limits JSON Example

Source: https://longhorn.io/docs/1.12.1/references/settings

Example JSON object for the 'System Managed CSI Components Resource Limits' setting. Keys are component names and values are Kubernetes ResourceRequirements with requests and limits. Only listed components are overridden; others use Longhorn defaults.

```json
{
  "csi-attacher": {
    "requests": {"cpu": "100m", "memory": "128Mi"},
    "limits": {"cpu": "200m", "memory": "256Mi"}
  },
  "csi-provisioner": {
    "requests": {"cpu": "100m", "memory": "128Mi"},
    "limits": {"cpu": "200m", "memory": "256Mi"}
  },
  "longhorn-csi-plugin": {
    "requests": {"cpu": "100m", "memory": "128Mi"},
    "limits": {"cpu": "200m", "memory": "256Mi"}
  },
  "node-driver-registrar": {
    "requests": {"cpu": "50m", "memory": "64Mi"},
    "limits": {"cpu": "100m", "memory": "128Mi"}
  }
}
```

--------------------------------

### fleet.yaml: Specify Longhorn Helm chart

Source: https://longhorn.io/docs/1.12.1/deploy/install/install-with-fleet

Configures Fleet to install the Longhorn Helm chart from the Longhorn repository, with version v1.12.1 as an example.

```yaml
helm:
  repo: https://charts.longhorn.io
  chart: longhorn
  version: v1.12.1 # Replace with the Longhorn version you'd like to install or upgrade to
  releaseName: longhorn

```

--------------------------------

### Create Longhorn StorageClass with kubectl

Source: https://longhorn.io/docs/1.12.1/nodes-and-volumes/volumes/create-volumes

Run this command to create the Longhorn StorageClass from the official example file. This is the first step in the volume creation workflow.

```bash
kubectl create -f https://raw.githubusercontent.com/longhorn/longhorn/v1.12.1/examples/storageclass.yaml

```

--------------------------------

### Example: complete workflow with verification

Source: https://longhorn.io/docs/1.12.1/deploy/accessing-the-ui/longhorn-ingress-traefik

Shows the complete workflow from creating the auth secret to verifying the Ingress with curl, including expected output for unauthorized and authorized requests.

```bash
$ USER=foo; PASSWORD=bar; echo "${USER}:$(openssl passwd -stdin -apr1 <<< ${PASSWORD})" > auth
$ kubectl -n longhorn-system create secret generic basic-auth --from-file=auth
secret/basic-auth created

# (After applying middlewares and ingress manifests)

$ kubectl -n longhorn-system get ingress
NAME               CLASS     HOSTS   ADDRESS      PORTS   AGE
longhorn-ingress   traefik   * 10.0.2.15    80      15s

$ curl -I http://10.0.2.15/
HTTP/1.1 401 Unauthorized
Www-Authenticate: Basic realm="traefik"

$ curl -u foo:bar -I http://10.0.2.15/
HTTP/1.1 200 OK

```

--------------------------------

### Update and install a valid linux-modules-extra version (Ubuntu 22.04)

Source: https://longhorn.io/docs/1.12.1/troubleshoot/troubleshooting

These commands update the package list and install a specific version of the Linux kernel extra modules package that is known to be available. This is provided as a resolution for the previous error, using version 5.15.0-76-generic as an example.

```bash
apt update -y
apt install -y linux-modules-extra-5.15.0-76-generic
```

--------------------------------

### Check Danger Zone setting application with kubectl get setting

Source: https://longhorn.io/docs/1.12.1/references/settings

Check whether a Danger Zone setting has been applied by inspecting the APPLIED field. The output shows the setting priority-class with value longhorn-critical and APPLIED true.

```bash
~# kubectl -n longhorn-system get setting priority-class
NAME             VALUE               APPLIED   AGE
priority-class   longhorn-critical   true      3h26m

```

--------------------------------

### Load iscsi_tcp module

Source: https://longhorn.io/docs/1.12.1/deploy/install

Ensure the iscsi_tcp module is loaded before the iscsid service starts. This is generally done automatically with the package installation, but can be done manually with this command.

```bash
modprobe iscsi_tcp

```

--------------------------------

### Set up NFS Backupstore

Source: https://longhorn.io/docs/1.12.1/snapshots-and-backups/backup-and-restore/set-backup-target

Use an NFS URL to set up a backupstore. The NFS server must support NFSv4. If nfsOptions is not specified, Longhorn uses default mount options: actimeo=1,soft,timeo=300,retry=2. Custom options can be provided via the nfsOptions query parameter, and Longhorn will adjust them to ensure operations fail instead of hanging.

```text
nfs://longhorn-test-nfs-svc.default:/opt/backupstore

```

```text
nfs://longhorn-test-nfs-svc.default:/opt/backupstore?nfsOptions=rw,nolock

```

```text
nfs://longhorn-test-nfs-svc.default:/opt/backupstore?nfsOptions=timeo=600

```

--------------------------------

### Rollback Longhorn with Helm

Source: https://longhorn.io/docs/1.12.1/deploy/upgrade/longhorn-manager

Commands to rollback to a previously installed Longhorn revision using Helm. First get the previous revision with 'helm history longhorn', then rollback or upgrade to the previous version.

```bash
# get previous installed Longhorn REVISION
helm history longhorn
helm rollback longhorn [REVISION]

# or
helm upgrade longhorn longhorn/longhorn --namespace longhorn-system --version [previous installed version]

```

--------------------------------

### Get Longhorn services with kubectl

Source: https://longhorn.io/docs/1.12.1/deploy/accessing-the-ui

Retrieve the Longhorn services in the longhorn-system namespace. The output shows the longhorn-frontend service with a ClusterIP of 10.20.245.110, which is used to access the UI. Starting with Longhorn v0.8.0, the UI service type is ClusterIP instead of LoadBalancer.

```bash
kubectl -n longhorn-system get svc

```

```text
NAME                TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE
longhorn-backend    ClusterIP   10.20.248.250   <none>        9500/TCP   58m
longhorn-frontend   ClusterIP   10.20.245.110   <none>        80/TCP     58m

```

--------------------------------

### Verify longhornctl installation

Source: https://longhorn.io/docs/1.12.1/advanced-resources/longhornctl/install-longhornctl

Checks the installed longhornctl version to confirm the installation succeeded.

```bash
longhornctl version
```

--------------------------------

### Create Pod with PVC using kubectl

Source: https://longhorn.io/docs/1.12.1/nodes-and-volumes/volumes/create-volumes

Run this command to create the Pod and PVC example. It launches a Pod named volume-test and a PVC named longhorn-volv-pvc.

```bash
kubectl create -f https://raw.githubusercontent.com/longhorn/longhorn/v1.12.1/examples/pod_with_pvc.yaml

```

--------------------------------

### Example output of ps aux | grep k3s

Source: https://longhorn.io/docs/1.12.1/advanced-resources/os-distro-specific/csi-on-k3s

Sample output showing the k3s server process with its --data-dir argument.

```bash
$ ps uax | grep k3s
root      4160  0.0  0.0  51420  3948 pts/0    S+   00:55   0:00 sudo /usr/local/bin/k3s server --data-dir /opt/test/kubelet
root      4161 49.0  4.0 259204 164292 pts/0   Sl+  00:55   0:04 /usr/local/bin/k3s server --data-dir /opt/test/kubelet
```

--------------------------------

### Verify Longhorn installation

Source: https://longhorn.io/docs/1.12.1/deploy/install/install-with-argocd

Check the status of the Longhorn pods in the 'longhorn-system' namespace to confirm the installation was successful.

```bash
kubectl -n longhorn-system get pod

```

--------------------------------

### Check prerequisites for V2 Data Engine with --enable-spdk

Source: https://longhorn.io/docs/1.12.1/deploy/install

Runs the preflight check with --enable-spdk to validate additional V2 requirements such as CPU instructions, HugePages, and SPDK kernel modules.

```bash
./longhornctl check preflight --enable-spdk

```

--------------------------------

### Install Gateway API CRDs

Source: https://longhorn.io/docs/1.12.1/deploy/accessing-the-ui/longhorn-httproute

Installs the Gateway API CRDs (v1.2.0) required before creating an HTTPRoute for Longhorn.

```bash
kubectl apply -f https://github.com/kubernetes-sigs/gateway-api/releases/download/v1.2.0/standard-install.yaml

```

--------------------------------

### Create HelmRepository for Longhorn

Source: https://longhorn.io/docs/1.12.1/deploy/install/install-with-flux

Create a namespace and a HelmRepository custom resource pointing to the Longhorn Helm chart URL, then apply it.

```bash
kubectl create ns longhorn-system
flux create source helm longhorn-repo \
  --url=https://charts.longhorn.io \
  --namespace=longhorn-system \
  --export > helmrepo.yaml
kubectl apply -f helmrepo.yaml

```

--------------------------------

### Generate Kustomize overlay for MinIO credentials

Source: https://longhorn.io/docs/1.12.1/snapshots-and-backups/backup-and-restore/set-backup-target

Runs the script to generate a Kustomize overlay for MinIO credentials. The overlay is created under deploy/backupstores/overlays/generated-credentials/minio.

```bash
./scripts/generate-backupstore-credentials.sh minio --no-encode

```