Configuring ephemeral disk support (VMware)

Using the IBM® Cloud Manager with OpenStack command-line interface, you can add ephemeral disks during the deployment process of a virtual machine.

About this task

If you want to add the disks during deployment, choose one of the following methods.

Example

Method 1: Specify the "--ephemeral" option when you create a flavor. For example, nova flavor-create –ephemeral SIZE_GB FLAVOR_NAME auto RAM DISK VCPUS. Then, deploy a virtual machine with this flavor. For example, nova boot –flavor FALVOR_ID –image IMAGE INSTANCE_NAME.
Method 2: Specify the block device information when you deploy a virtual machine, "--block-device" option with detailed keys and values. For example, nova boot –flavor FALVOR_ID –image IMAGE -block-device source=blank, dest=local, format=ext4, size=2, bus=ide, type=disk INSTANCE_NAME. The flavor that is used in this situation also needs a flavor with ephemeral, such as the flavor used in step 1.

You can also add disks when you resize the virtual machine. You can choose to resize a virtual machine from no-ephemeral-disk status to with-ephemeral-disk status. Likewise, you can resize a virtual machine from with-ephemeral-disk status to no-ephemeral-disk status. For example:

Deploy a virtual machine with no ephemeral disk:
1. Create a flavor without ephemeral disk.
```
nova flavor-create SIZE_GB FLAVOR_NAME auto RAM DISK VCPUS
```
2. Check the flavor that is created. The ephemeral is "0" in the list.
```
nova flavor-show FLAVOR_ID
```
3. Deploy the virtual machine.
```
nova boot –flavor FLAVOR_ID –image IMAGE_ID INSTANCE_NAME
```
Resize a virtual machine from no-ephemeral-disk status to with-ephemeral-disk status:
1. Create a flavor with ephemeral disk.
```
nova flavor-create –ephemeral SIZE_GB FLAVOR_NAME auto RAM DISK VCPUS
```
2. Resize the virtual machine that is created in last step to an ephemeral disk.
```
nova resize INSTANCE_NAME
```
Confirm the resize operation in the previous step.
```
nova resize-confirm INSTANCE_NAME
```
Check that the instance changed to one with ephemeral disk. Use the following command to see that the flavor details changed to the size you specified (SIZE_GB).
```
nova show INSTANCE_NAME
```

Note:

If you use block device information, multiple ephemeral disks are supported.
You can add ephemeral disks to virtual machine disks (VMDK) or when you deploy image templates.
You can resize one ephemeral disk only.

Restriction: After the ephemeral disk is attached to the VM, you must create partitions and format the file system (such as ext3) before the disks can be used to store data.