Create a cloud instance (3/5)
persistent ephemeral security

Create a cloud instance (3/5)

Before you create an instance you must be sure you have created a key pair. If you have a key pair and you need to know a little about selecting the right storage before you launch a new instance. You can configure a new ephemeral instance or a persistent instance. If you want to know the differences between these two, click the following link: How to choose the right OpenStack Storage. Once you've decided upon which storage you want to use, you can create your instance. In this guide we will help you through the process of creating an ephemeral or a persistent instance.

Creating a Persistent Instance

For creating a persistent instance, you need to create a bootable volume.

  1. Log on to the OpenStack dashboard and choose your project.
  2. Click Compute followed by Volumes.
  3. Select Create Volume:
    1. Specify your new volume name and optionally a description.
    2. Type: Select low, medium or high.
    3. Size: The minimum for a linux bootable volume is 10GB and for a Windows bootable volume is 30GB.
    4. Select Image from the Volume Source drop down list.
  4. Use image as a source: Choose the image you like to use.
  5. Availability Zone: Any Availability Zone will do for most use cases.
    1. If you select a specific Availability Zone, you will need to make sure that your bootable volume remains in the same availability zone as the instance you’re going to create with the bootable volume.
  6. Click on Create Volume.

Now that you created your bootable volume, you can create your Persistent Instance.

  1. Log on to the OpenStack dashboard and choose your project.
  2. Click Compute followed by Instances.
  3. Now select Launch Instance in the top right corner:
    1. Select the Availability Zone for your instance.
    2. Specify an Instance Name.
    3. Select a Flavor from the drop down box.
    4. The default Instance Count is one. Increase this number if you need to start multiple instances.
    5. Instance Boot Source: For a Persistent Instance select Boot from volume from the drop down list.
    6. Volume: Select the volume you created earlier.
  4. Click on Access & Security.
    1. Select the Keypair that you created earlier and select a Security Group.
      • You can add more than one Key Pair.
  5. Click on Networking.
  6. Select one or more of your Available Networks and add it to your Selected Instances.
  7. Optional: Add the following in the Post-Creation tab inside the Customization Script field:
    
          #cloud-config
          hostname: instance1
          fqdn: instance1.fqdn.test
          manage_etc_hosts: true
        
  8. Now click Launch, to start your instance.

Your Persistent Instance has been created. You are able to see your instance under the Instances overview.

Creating an Ephemeral Instance

  1. Log on to the OpenStack dashboard and choose your project.
  2. Click Compute followed by Instances.
  3. Click Launch Instance in the top right corner:
    1. Select the Availability Zone for your instance.
    2. Specify an Instance Name.
    3. Select a Flavor from the drop down box.
    4. The default Instance Count is one. Increase this number if you need to start multiple instances.
    5. Instance Boot Source: For an Ephemeral Instance select Boot From Image from the drop down list.
    6. Image Name: Select one of the images from the drop down list.
  4. Click on Access & Security.
    1. Select the Keypair that you created earlier and select a Security Group.
      • You can add more than one Key Pair.
  5. Click on Networking.
  6. Select one or more of your Available Networks and add it to your Selected Instances.
  7. Add the following in the Post-Creation tab inside the Customization Script field:
    
          #cloud-config
          hostname: instance1
          fqdn: instance1.fqdn.test
          manage_etc_hosts: true
        
  8. Now click Launch, to start your instance.

Your Ephemeral Instance has been created. You are able to see your instance under the Instances overview.

Assign a security group

  1. Log on to the Openstack dashboard and open your project.
  2. Click on the instances tab to view all your instances.
  3. Click on the down arrow right of the Create Snapshot button to view all the available options.
  4. Select edit security groups.
  5. A new tab opens and you can see your available security groups you made earlier.
  6. Click the one you want by clicking on the + and save. You can add more than one security group.

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Allocate a floating IP to an instance (4/5)

When you create an OpenStack instance, it receives a private IP address. Your instance is accessible for other instances with this private IP address . If you want to access your instance(s) over the internet, you'll need to assign a (floating) IP to these instances. A floating IP is an IP address on a external network. A floating IP address gives access to an instance to a private network from an external network.