As Cinder volumes can only be attached to one host at a time, you need to detach it from one instance before attaching it to another. To detach a volume, we use another Nova client option called volume-detach.
To begin with, ensure you are logged in to the Ubuntu host that has access to Nova client tools. If using the Vagrant environment that accompanies the book, you can access these tools from the controller node:
vagrant ssh controller
This recipe assumes you have created an openrc file. To create an openrc file on each node where you need it, open a text file named openrc, and add the following contents:
export OS_TENANT_NAME=cookbook export OS_USERNAME=admin export OS_PASSWORD=openstack export OS_AUTH_URL=https://192.168.100.200:5000/v2.0/ export OS_KEY=/path/to/cakey.pem export OS_CACERT=/path/to/ca.pem
These packages can be installed using the following commands:
sudo apt-get update sudo apt-get install python-novaclient