Chapter 6. Deploy the edge without storage
You can deploy a distributed compute node cluster without Block storage at edge sites if you use the Object Storage service (swift) as a back end for the Image service (glance) at the central location. A site deployed without block storage cannot be updated later to have block storage due to the differing role and networking profiles for each architecture.
The following procedure uses lvm as the back end for the Block Storage service (cinder), which is not supported for production. You must deploy a certified block storage solution as a back end for the Block Storage service.
6.1. Deploying edge nodes without storage
You can deploy edge compute nodes that will use the central location as the control plane. This procedure shows how to add a new DCN stack to your deployment and reuse the configuration from the existing heat stack to create new environment files. The first heat stack deploys an overcloud within a centralized datacenter. Create additional heat stacks to deploy Compute nodes to a remote location.
6.1.1. Configuring the distributed compute node environment files
Generate the configuration files that the DCN sites require:
openstack overcloud export \ --config-download-dir /var/lib/mistral/central \ --stack central --output-file ~/dcn-common/central-export.yamlImportant
This procedure creates a new
central-export.yamlenvironment file and uses the passwords in the
plan-environment.yamlfile from the overcloud. The
central-export.yamlfile contains sensitive security data. To improve security, you can remove the file when you no longer require it.Important
When you specify the directory for the
--config-download-diroption, use the central hub Ansible configuration that director creates in
/var/lib/mistralduring deployment. Do not use Ansible configuration that you manually generate with the
openstack overcloud config downloadcommand. The manually generated configuration lacks certain files that are created only during a deployment operation.
Generate roles for the edge location using roles appropriate for your environment:
openstack overcloud roles generate Compute -o ~/dcn0/dcn0_roles.yaml
If you are using ML2/OVS for networking overlay, you must edit the roles file that you created to include the
... - OS::TripleO::Services::MySQLClient - OS::TripleO::Services::NeutronBgpVpnBagpipe + - OS::TripleO::Services::NeutronDhcpAgent + - OS::TripleO::Services::NeutronMetadataAgent - OS::TripleO::Services::NeutronLinuxbridgeAgent - OS::TripleO::Services::NeutronVppAgent - OS::TripleO::Services::NovaAZConfig - OS::TripleO::Services::NovaCompute ...
For more information, see Preparing for a routed provider network.
6.1.2. Deploying the Compute nodes to the DCN site
This procedure uses the
Compute role to deploy Compute nodes to an availability zone (AZ) named
dcn0. In a distributed compute node (DC) context, this role is used for sites without storage.
Review the overrides for the distributed compute (DCN) site in dcn0/overrides.yaml
parameter_defaults: ComputeCount: 3 ComputeFlavor: baremetal ComputeSchedulerHints: 'capabilities:node': '0-compute-%index%' NovaAZAttach: false
Create a new file called
~/dcn0directory with the following contents:
resource_registry: OS::TripleO::Services::NovaAZConfig: /usr/share/openstack-tripleo-heat-templates/deployment/nova/nova-az-config.yaml parameter_defaults: NovaComputeAvailabilityZone: dcn0 RootStackName: dcn0
Retrieve the container images for the DCN Site:
sudo openstack tripleo container image prepare \ --environment-directory dcn0 \ -r ~/dcn0/roles_data.yaml \ -e ~/dcn-common/central-export.yaml \ -e ~/containers-prepare-parameter.yaml \ --output-env-file ~/dcn0/dcn0-images-env.yaml
Run the deploy.sh deployment script for dcn0:
#!/bin/bash STACK=dcn0 source ~/stackrc time openstack overcloud deploy \ --stack $STACK \ --templates /usr/share/openstack-tripleo-heat-templates/ \ -e /usr/share/openstack-tripleo-heat-templates/environments/nova-az-config.yaml \ -e ~/dcn-common/central-export.yaml \ -e ~/dcn0/dcn0-images-env.yaml \ -e ~/dcn0/site-name.yaml \ -e ~/dcn0/overrides.yaml
If you deploy additional edge sites that require edits to the
network_data.yamlfile, you must execute a stack update at the central location.
You must include heat templates for the configuration of networking in your
openstack overcloud deploy command. Designing for edge architecture requires spine and leaf networking. See Spine Leaf Networking for more details.