Set up a Private OpenStack Cloud using Simplestreams

Overview

When Juju bootstraps a cloud, it needs two critical pieces of information: 1. The uuid of the image to use when starting new compute instances. 1. The URL from which to download the correct version of a tools tarball.

This necessary information is stored in a json metadata format called "simplestreams". For supported public cloud services such as Amazon Web Services, HP Cloud, Azure, etc, no action is required by the end user. However, those setting up a private cloud, or who want to change how things work (eg use a different Ubuntu image), can create their own metadata.

This page explains how to use Juju and additional tools to generate this simplestreams metadata and configure OpenStack to use them.

Requirements

  • python-openstackclient
  • python-swiftclient

Generating the metadata

To begin, create a directory to hold the generted metadata

mkdir -p ~/simplestreams/images

Now, if necessary, source the nova.rc file for your cloud:

. ~/nova.rc

We can now determine the region name for the cloud by running:

openstack endpoint list

The region name will be required in a later step.

Next, enter the following command to determine the Image ID of the cloud image in glance:

openstack image list -f value -c ID

Again, take note of this image ID which we will use in the next step

Note: If you have images for multiple different series of Ubuntu, make sure you keep track of which series name matches which image ID. The value $IMAGE_ID will apply to the image ID of the image for the particular series you are specifying and $OS_SERIES will be the series name ("trusty", "xenial", etc.).

We can now use Juju to generate the metadata:

juju metadata generate-image -d ~/simplestreams -i $IMAGE_ID -s $OS_SERIES -r $REGION -u http://$KEYSTONE_IP:5000/v2.0/

substituting in the appropriate values:

  • $IMAGE_ID - The image ID we are creating metadata for.
  • $OS_SERIES - The appropriate series this image relates to (e.g. Xenial).
  • $REGION - The region name of the cloud.
  • $KEYSTONE_IP - The address of the cloud's keystone server.

If you have images for multiple series of Ubuntu, run this command again for each series substituting $OS_SERIES with the series name and $IMAGE_ID with the image ID that matches that series.

To verify that the correct metadata files have been generated, you may run:

ls ~/simplestreams/*/streams/*

You should see .json files for the images.

Upload the Simplestreams Metadata to Swift

Enter the following command to create a new container for the Simplestreams metadata:

openstack container create simplestreams

You can verify the container has been created by running:

openstack container list

Enter the following command to view the status of the container:

openstack container show simplestreams

Notice the Objects: line. You should see that the container does not contain any objects.

To upload the Simplestreams metadata to the container:

cd ~/simplestreams
swift upload simplestreams *

Check the status of the container:

swift stat simplestreams

Notice the Objects: line again. You should see that the container now contains objects Currently, there are no Read or Write ACLs. This is essentially a private container.

Enter the following command to add a Read ACL that will make the container publicly accessible:

swift post simplestreams --read-acl .r:*

Create a simplestream service

Enter the following command to create a new service in the Keystone service catalog for simplestreams:

openstack service create --name product-stream --description “Product Simple Stream” product-streams

We also need to register an endpoint with the Simplestreams service. Enter the following command to determine the project ID for the admin user:

openstack user show admin -f value -c project_id

This value will be used to replace the string $(tenant_id)s when we construct the Swift URL in a future step.

Enter the following command to determine the URL in Swift for the Simplestreams objects:

openstack endpoint show object-store

Notice the URL for the Object Store. Replace the string $(tenant_id)s with the project ID obtained in the previous step. We will refer to this modified URL as the 'SWIFT_URL'.

Enter the following command to register the endpoint with the Simplestreams service:

openstack endpoint create --region $REGION --publicurl $SWIFT_URL/simplestreams/images \
   --internalurl $SWIFT_URL/simplestreams/images \
   --publicurl $SWIFT_URL/simplestreams/images product-streams

Bootstrap with Juju

Now the simplestream service is registered and running you can create a controller on this cloud with the juju bootstrap command. The 

juju bootstrap <cloud> <controller name> --config tools-metadata-url=xxx.xxx.xx.xx

The metadata-url specified with the config option should point to the endpoint you created in the previous step.

If there are multiple possible networks available to the cloud, it is also necessary to specify the network label or UUID for Juju to use:

juju bootstrap openstack
--config image-metadata-url=http://xxx.xxx.xxx.xxx/simplestream/images/
--config network=d54a6557-e114-4e26-98b8-55c814fb938a