Local Path Provisioner provides a way for the Kubernetes users to utilize the local storage in each node. Based on the user configuration, the Local Path Provisioner will create hostPath
based persistent volume on the node automatically. It utilizes the features introduced by Kubernetes Local Persistent Volume feature, but make it a simpler solution than the built-in local
volume feature in Kubernetes.
Dynamic provisioning the volume using host path.
- Currently the Kubernetes Local Volume provisioner cannot do dynamic provisioning for the host path volumes.
- No support for the volume capacity limit currently.
- The capacity limit will be ignored for now.
- Only support
hostPath
Kubernetes v1.12+.
In this setup, the directory /opt/local-path-provisioner
will be used across all the nodes as the path for provisioning (a.k.a, store the persistent volume data). The provisioner will be installed in local-path-storage
namespace by default.
kubectl apply -f https://raw.githubusercontent.com/rancher/local-path-provisioner/master/deploy/local-path-storage.yaml
After installation, you should see something like the following:
$ kubectl -n local-path-storage get pod
NAME READY STATUS RESTARTS AGE
local-path-provisioner-d744ccf98-xfcbk 1/1 Running 0 7m
Check and follow the provisioner log using:
$ kubectl -n local-path-storage logs -f local-path-provisioner-d744ccf98-xfcbk
Create a hostPath
backed Persistent Volume and a pod uses it:
kubectl create -f https://raw.githubusercontent.com/rancher/local-path-provisioner/master/examples/pvc.yaml
kubectl create -f https://raw.githubusercontent.com/rancher/local-path-provisioner/master/examples/pod.yaml
You should see the PV has been created:
$ kubectl get pv
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
pvc-bc3117d9-c6d3-11e8-b36d-7a42907dda78 2Gi RWO Delete Bound default/local-path-pvc local-path 4s
The PVC has been bound:
$ kubectl get pvc
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
local-path-pvc Bound pvc-bc3117d9-c6d3-11e8-b36d-7a42907dda78 2Gi RWO local-path 16s
And the Pod started running:
$ kubectl get pod
NAME READY STATUS RESTARTS AGE
volume-test 1/1 Running 0 3s
Write something into the pod
kubectl exec volume-test -- sh -c "echo local-path-test > /data/test"
Now delete the pod using
kubectl delete -f https://raw.githubusercontent.com/rancher/local-path-provisioner/master/examples/pod.yaml
After confirm that the pod is gone, recreated the pod using
kubectl create -f https://raw.githubusercontent.com/rancher/local-path-provisioner/master/examples/pod.yaml
Check the volume content:
$ kubectl exec volume-test cat /data/test
local-path-test
Delete the pod and pvc
kubectl delete -f https://raw.githubusercontent.com/rancher/local-path-provisioner/master/examples/pod.yaml
kubectl delete -f https://raw.githubusercontent.com/rancher/local-path-provisioner/master/examples/pvc.yaml
The volume content stored on the node will be automatically cleaned up. You can check the log of local-path-provisioner-xxx
for details.
Now you've verified that the provisioner works as expected.
The configuration of the provisioner is a json file config.json
, stored in the a config map, e.g.:
kind: ConfigMap
apiVersion: v1
metadata:
name: local-path-config
namespace: local-path-storage
data:
config.json: |-
{
"nodePathMap":[
{
"node":"DEFAULT_PATH_FOR_NON_LISTED_NODES",
"paths":["/opt/local-path-provisioner"]
},
{
"node":"yasker-lp-dev1",
"paths":["/opt/local-path-provisioner", "/data1"]
},
{
"node":"yasker-lp-dev3",
"paths":[]
}
]
}
nodePathMap
is the place user can customize where to store the data on each node.
- If one node is not listed on the
nodePathMap
, and Kubernetes wants to create volume on it, the paths specified inDEFAULT_PATH_FOR_NON_LISTED_NODES
will be used for provisioning. - If one node is listed on the
nodePathMap
, the specified paths inpaths
will be used for provisioning.- If one node is listed but with
paths
set to[]
, the provisioner will refuse to provision on this node. - If more than one path was specified, the path would be chosen randomly when provisioning.
- If one node is listed but with
The configuration must obey following rules:
config.json
must be a valid json file.- A path must start with
/
, a.k.a an absolute path. - Root directory(
/
) is prohibited. - No duplicate paths allowed for one node.
- No duplicate node allowed.
The provisioner supports automatic configuration reloading. Users can change the configuration using kubectl apply
or kubectl edit
with config map local-path-config
. There is a delay between when the user updates the config map and the provisioner picking it up.
When the provisioner detects the configuration changes, it will try to load the new configuration. Users can observe it in the log
time="2018-10-03T05:56:13Z" level=debug msg="Applied config: {"nodePathMap":[{"node":"DEFAULT_PATH_FOR_NON_LISTED_NODES","paths":["/opt/local-path-provisioner"]},{"node":"yasker-lp-dev1","paths":["/opt","/data1"]},{"node":"yasker-lp-dev3"}]}"
If the reload fails, the provisioner will log the error and continue using the last valid configuration for provisioning in the meantime.
time="2018-10-03T05:19:25Z" level=error msg="failed to load the new config file: fail to load config file /etc/config/config.json: invalid character '#' looking for beginning of object key string"
time="2018-10-03T05:20:10Z" level=error msg="failed to load the new config file: config canonicalization failed: path must start with / for path opt on node yasker-lp-dev1"
time="2018-10-03T05:23:35Z" level=error msg="failed to load the new config file: config canonicalization failed: duplicate path /data1 on node yasker-lp-dev1
time="2018-10-03T06:39:28Z" level=error msg="failed to load the new config file: config canonicalization failed: duplicate node yasker-lp-dev3"
Before uninstallation, make sure the PVs created by the provisioner have already been deleted. Use kubectl get pv
and make sure no PV with StorageClass local-path
.
To uninstall, execute:
kubectl delete -f https://raw.githubusercontent.com/rancher/local-path-provisioner/master/deploy/local-path-storage.yaml
Copyright (c) 2014-2018 Rancher Labs, Inc.
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