[](https://bestpractices.coreinfrastructure.org/en/projects/3523)
See [roadmap](https://github.com/orgs/openebs/projects/10), [e2e-wiki](https://github.com/openebs/zfs-localpv/wiki/ZFS-LocalPV-e2e-test-cases) and [e2e-test](https://github.com/openebs/e2e-tests/projects/7).
Go to each node and create the ZFS Pool, which will be used for provisioning the volumes. You can create the Pool of your choice, it can be striped, mirrored or raidz pool.
Configure the custom topology keys (if needed). This can be used for many purposes like if we want to create the PV on nodes in a particuler zone or building. We can label the nodes accordingly and use that key in the storageclass for taking the scheduling decesion:
**NOTE:** For some Kubernetes distributions, the `kubelet` directory must be changed at all relevant places in the YAML powering the operator (both the `openebs-zfs-controller` and `openebs-zfs-node`).
- For `microk8s`, we need to change the kubelet directory to `/var/snap/microk8s/common/var/lib/kubelet/`, we need to replace `/var/lib/kubelet/` with `/var/snap/microk8s/common/var/lib/kubelet/` at all the places in the operator yaml and then we can apply it on microk8s.
Also the dataset provided under `poolname` must exist on *all the nodes* with the name given in the storage class. Check the doc on [storageclasses](docs/storageclasses.md) to know all the supported parameters for ZFS-LocalPV
Here please note that we are providing `volblocksize` instead of `recordsize` since we will create a ZVOL, for which we can choose the blocksize with which we want to create the block device. Here, please note that for ZFS, volblocksize should be power of 2.
Here please note that we are providing `recordsize` which will be used to create the ZFS datasets, which specifies the maximum block size for files in the zfs file system. The recordsize has to be power of 2 for ZFS datasets.
The above storage class tells that ZFS pool "zfspv-pool" is available on nodes zfspv-node1 and zfspv-node2 only. The ZFS driver will create volumes on those nodes only.
Please note that the provisioner name for ZFS driver is "zfs.csi.openebs.io", we have to use this while creating the storage class so that the volume provisioning/deprovisioning request can come to ZFS driver.
The ZFS driver has its own scheduler which will try to distribute the PV across the nodes so that one node should not be loaded with all the volumes. Currently the driver supports two scheduling algorithms: VolumeWeighted and CapacityWeighted, in which it will try to find a ZFS pool which has less number of volumes provisioned in it or less capacity of volume provisioned out of a pool respectively, from all the nodes where the ZFS pools are available. To know about how to select scheduler via storage-class See [this](https://github.com/openebs/zfs-localpv/blob/HEAD/docs/storageclasses.md#storageclass-with-k8s-scheduler).
Once it is able to find the node, it will create a PV for that node and also create a ZFSVolume custom resource for the volume with the NODE information. The watcher for this ZFSVolume
CR will get all the information for this object and creates a ZFS dataset(zvol) with the given ZFS property on the mentioned node.
The scheduling algorithm currently only accounts for either the number of ZFS volumes or total capacity occupied from a zpool and does not account for other factors like available cpu or memory while making scheduling decisions.
So if you want to use node selector/affinity rules on the application pod, or have cpu/memory constraints, kubernetes scheduler should be used.
To make use of kubernetes scheduler, you can set the `volumeBindingMode` as `WaitForFirstConsumer` in the storage class.
This will cause a delayed binding, i.e kubernetes scheduler will schedule the application pod first and then it will ask the ZFS driver to create the PV.
The driver will then create the PV on the node where the pod is scheduled.
Please note that once a PV is created for a node, application using that PV will always get scheduled to that particular node only, as PV will be sticky to that node.
The scheduling algorithm by ZFS driver or kubernetes will come into picture only during the deployment time. Once the PV is created,
the application can not move anywhere as the data is there on the node where the PV is.
Create a PVC using the storage class created for the ZFS driver. Here, the allocated volume size will be rounded off to the nearest Mi or Gi notation, check the [faq](./docs/faq.md#7-why-the-zfs-volume-size-is-different-than-the-reqeusted-size-in-pvc) section for more details.
If we are using the immediate binding in the storageclass then we can check the kubernetes resource for the corresponding zfs volume, other wise in late binding case, we can check the same after pod has been scheduled.
The ZFS driver will create a ZFS dataset(or zvol as per fstype in the storageclass) on the node zfspv-node1 for the mentioned ZFS pool and the dataset name will same as PV name.
Go to the node zfspv-node1 and check the volume :-
ZFS Volume Property can be changed like compression on/off can be done by just simply editing the kubernetes resource for the corresponding zfs volume by using below command :
for deprovisioning the volume we can delete the application which is using the volume and then we can go ahead and delete the pv, as part of deletion of pv this volume will also be deleted from the ZFS pool and data will be freed.
Follow below practice while running kernel ZFS along with cStor on the same set of nodes
- Disable zfs-import-scan.service service that will avoid importing all pools by scanning all the available devices in the system, disabling scan service will avoid importing pools that are not created by kernel. Disabling scan service will not cause harm since zfs-import-cache.service is enabled and it is the best way to import pools by looking at cache file during boot time.
```sh
sudo systemctl stop zfs-import-scan.service
sudo systemctl disable zfs-import-scan.service
```
- Always maintain upto date /etc/zfs/zpool.cache while performing operations any day2 operations on zfs pools(zpool set cachefile=/etc/zfs/zpool.cache <pooldatasetname>).
Note: Following above two step kernel ZFS will not import the pools created by cStor
