Version: 3.1

Volume Lifecycle Basics with CSI

This section provides instructions for managing Portworx CSI volumes on Nomad.

Dynamic volume creation

The following steps will allow you to dynamically provision a Portworx CSI volume:

Create a file named volume.hcl with the following content:

id           = "volume-1"
name         = "database"
type         = "csi"
plugin_id    = "portworx"
capacity_min = "1G"
capacity_max = "1G"

capability {
  access_mode     = "single-node-writer"
  attachment_mode = "file-system"
}

Create a volume using thevolume.hcl file you just created:
```
nomad volume create volume.hcl
```
Verify the volume creation; if successful, the status should be xxxxx:
```
nomad volume status
```

Registering pre-provisioned volumes

To register a pre-provisioned volume, you must first create a volume on one of the nodes. This example uses the Portworx job to find which alloc to run your commands on.

Get the status of the Portworx job:

nomad job status portworx

Grab a running allocation ID from the table listed with the previous command. This example uses 8d76fdfc from the output:

Allocations
ID        Node ID   Task Group  Version  Desired  Status   Created    Modified
8d76fdfc  58c745d0  portworx    0        run      running  10d5h ago  10d5h ago
a75f6340  e374e687  portworx    0        run      running  10d5h ago  10d5h ago
ff166433  6e130136  portworx    0        run      running  10d5h ago  10d5h ago

Create a volume by executing the following pxctl command in the 8d76fdfc allocation:
```
nomad alloc exec 8d76fdfc /opt/pwx/bin/pxctl volume create volume1
Volume successfully created: 1055712112955862813
```
Note the volume ID in the command output above. This will be used in a future step. It is 1055712112955862813 in this example.

note

If the command above failed with Access denied token is empty, you must setup a pxctl context on that machine.

Create a volume registration file volume-register.hcl:

id           = "volume-2"
name         = "database"
type         = "csi"
plugin_id    = "portworx"
external_id  = "1055712112955862813"

capability {
  access_mode     = "single-node-writer"
  attachment_mode = "file-system"
}

Sharedv4 volume creation

Perform the following steps to dynamically provision a sharedv4 Portworx CSI volume:

Create a file volume-shared.hcl with the following content:

id           = "volume-2"
name         = "database"
type         = "csi"
plugin_id    = "portworx"
capacity_min = "1G"
capacity_max = "1G"

capability {
  access_mode     = "multi-node-multi-writer"
  attachment_mode = "file-system"
}

Create a volume using the above file:
```
nomad volume create volume-shared.hcl
```
List the volume status to see it:
```
nomad volume status
```

Run a Nomad job with Portworx volumes

Create a nomad job configuration file job.hcl with the following contents:

job "mysql-server" {
  datacenters = ["dc1"]
  type        = "service"

  group "mysql-server" {
    count = 1

    volume "database" {
      attachment_mode = "file-system"
      access_mode     = "single-node-writer"
      type            = "csi"
      read_only       = false
      source          = "volume-1"
    }

    network {
      port "db" {
        static = 3306
      }
    }

    restart {
      attempts = 10
      interval = "5m"
      delay    = "25s"
      mode     = "delay"
    }

    task "mysql-server" {
      driver = "docker"

      volume_mount {
        volume      = "database"
        destination = "/srv"
        read_only   = false
      }

      env {
        MYSQL_ROOT_PASSWORD = "password"
      }

      config {
        image = "hashicorp/mysql-portworx-demo:latest"
        args  = ["--datadir", "/srv/mysql"]
        ports = ["db"]
      }

      resources {
        cpu    = 500
        memory = 1024
      }

      service {
        name = "mysql-server"
        port = "db"

        check {
          type     = "tcp"
          interval = "10s"
          timeout  = "2s"
        }
      }
    }
  }
}

Create a job with the above configuration:
```
nomad job run job.hcl
```
Check the status of your job. It should be running shortly after the image pull has finished:
```
nomad job status mysql-server
```
This setup can be cleaned up by stopping the job and and deleting the volume:
```
nomad job stop mysql-server 
nomad volume delete volume-1
```

Dynamic volume creation​

Registering pre-provisioned volumes​

Sharedv4 volume creation​

Run a Nomad job with Portworx volumes​

Dynamic volume creation

Registering pre-provisioned volumes

Sharedv4 volume creation

Run a Nomad job with Portworx volumes