Mayastor Kubectl Plugin

The Mayastor kubectl plugin can be used to view and manage 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

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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 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 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 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

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 <resource_name> <resource_id>

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> 

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 

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Limitations of kubectl plugin

• The plugin currently does not have authentication support.

• The plugin can operate only over HTTP.

Learn more