Kubectl Plugin

The Mayastor kubectl plugin can be used to view and manage Replicated PV Mayastor resources such as nodes, pools and volumes. It is also used for operations such as scaling the replica count of volumes.

Install kubectl plugin

• The Mayastor kubectl plugin is available for the Linux platform. The binary for the plugin can be found here.

• Add the downloaded Mayastor kubectl plugin under $PATH.

To verify the installation, execute:

Command

kubectl mayastor -V

Expected Output

kubectl-plugin 1.0.0

Use kubectl plugin to Retrieve Data

Sample command to use kubectl plugin:

USAGE:

kubectl-mayastor [OPTIONS] <SUBCOMMAND>

OPTIONS:

-h, --help

Print help information

-j, --jaeger <JAEGER>

Trace rest requests to the Jaeger endpoint agent

-k, --kube-config-path <KUBE_CONFIG_PATH>

Path to kubeconfig file

-n, --namespace <NAMESPACE>

Kubernetes namespace of mayastor service, defaults to mayastor [default: mayastor]

-o, --output <OUTPUT>

The Output, viz yaml, json [default: none]

-r, --rest <REST>

The rest endpoint to connect to

-t, --timeout <TIMEOUT>

Timeout for the REST operations [default: 10s]

-V, --version

Print version information

SUBCOMMANDS:

cordon 'Cordon' resources

drain 'Drain' resources

dump `Dump` resources

get 'Get' resources

help Print this message or the help of the given subcommand(s)

scale 'Scale' resources

uncordon 'Uncordon' resources

You can use the plugin with the following options:

Get Replicated PV Mayastor Volumes

Command

kubectl mayastor get volumes

Expected Output

ID REPLICAS TARGET-NODE ACCESSIBILITY STATUS SIZE

18e30e83-b106-4e0d-9fb6-2b04e761e18a 4 mayastor-1 nvmf Online 10485761

0c08667c-8b59-4d11-9192-b54e27e0ce0f 4 mayastor-2 <none> Online 10485761

Get Replicated PV Mayastor Pools

Command

kubectl mayastor get pools

Expected Output

ID TOTAL CAPACITY USED CAPACITY DISKS NODE STATUS MANAGED

mayastor-pool-1 5360320512 1111490560 aio:///dev/vdb?uuid=d8a36b4b-0435-4fee-bf76-f2aef980b833 kworker1 Online true

mayastor-pool-2 5360320512 2172649472 aio:///dev/vdc?uuid=bb12ec7d-8fc3-4644-82cd-dee5b63fc8c5 kworker1 Online true

mayastor-pool-3 5360320512 3258974208 aio:///dev/vdb?uuid=f324edb7-1aca-41ec-954a-9614527f77e1 kworker2 Online false

Get Replicated PV Mayastor Nodes

Command

kubectl mayastor get nodes

Expected Output

ID GRPC ENDPOINT STATUS

mayastor-2 10.1.0.7:10124 Online

mayastor-1 10.1.0.6:10124 Online

mayastor-3 10.1.0.8:10124 Online

note

All the above resource information can be retrieved for a particular resource using its ID. The command to do so is as follows:

kubectl mayastor get &lt;resource_name&gt; &lt;resource_id&gt;

Scale the Replica Count of a Volume

Command

kubectl mayastor scale volume <volume_id> <size>

Expected Output

Volume 0c08667c-8b59-4d11-9192-b54e27e0ce0f Scaled Successfully 🚀

Retrieve Resource in any of the Output Formats (Table, JSON, or YAML)

Table is the default output format.

Command

kubectl mayastor -ojson get <resource_type>

Expected Output

[{"spec":{"num_replicas":2,"size":67108864,"status":"Created","target":{"node":"ksnode-2","protocol":"nvmf"},"uuid":"5703e66a-e5e5-4c84-9dbe-e5a9a5c805db","topology":{"explicit":{"allowed_nodes":["ksnode-1","ksnode-3","ksnode-2"],"preferred_nodes":["ksnode-2","ksnode-3","ksnode-1"]}},"policy":{"self_heal":true}},"state":{"target":{"children":[{"state":"Online","uri":"bdev:///ac02cf9e-8f25-45f0-ab51-d2e80bd462f1?uuid=ac02cf9e-8f25-45f0-ab51-d2e80bd462f1"},{"state":"Online","uri":"nvmf://192.168.122.6:8420/nqn.2019-05.io.openebs:7b0519cb-8864-4017-85b6-edd45f6172d8?uuid=7b0519cb-8864-4017-85b6-edd45f6172d8"}],"deviceUri":"nvmf://192.168.122.234:8420/nqn.2019-05.io.openebs:nexus-140a1eb1-62b5-43c1-acef-9cc9ebb29425","node":"ksnode-2","rebuilds":0,"protocol":"nvmf","size":67108864,"state":"Online","uuid":"140a1eb1-62b5-43c1-acef-9cc9ebb29425"},"size":67108864,"status":"Online","uuid":"5703e66a-e5e5-4c84-9dbe-e5a9a5c805db"}}]

Retrieve Replica Topology for Specific Volumes

Command

kubectl mayastor get volume-replica-topology <volume_id>

Expected Output

ID NODE POOL STATUS CAPACITY ALLOCATED SNAPSHOTS CHILD-STATUS REASON REBUILD

a34dbaf4-e81a-4091-b3f8-f425e5f3689b io-engine-1 pool-1 Online 12MiB 0 B 12MiB <none> <none> <none>

warning

The plugin requires access to the Mayastor REST server for execution. It gets the master node IP from the kube-config file. In case of any failure, the REST endpoint can be specified using the ‘–rest’ flag.

List Available Volume Snapshots

Command

kubectl mayastor get volume-snapshots

Expected Output

ID TIMESTAMP SOURCE-SIZE ALLOCATED-SIZE TOTAL-ALLOCATED-SIZE SOURCE-VOL

25823425-41fa-434a-9efd-a356b70b5d7c 2023-07-07T13:20:17Z 10MiB 12MiB 12MiB ec4e66fd-3b33-4439-b504-d49aba53da26

Limitations of kubectl plugin

• The plugin currently does not have authentication support.
• The plugin can operate only over HTTP.

Learn more