The purpose of this section is to explain how to put Ansible modules together to use Ansible in a CloudStack context. You will find more usage examples in the details section of each module.
Ansible contains a number of extra modules for interacting with CloudStack based clouds. All modules support check mode, are designed to be idempotent, have been created and tested, and are maintained by the community.
Prerequisites for using the CloudStack modules are minimal. In addition to Ansible itself, all of the modules require the python library ``cs`` https://pypi.org/project/cs/
..note:: cs also includes a command line interface for ad-hoc interaction with the CloudStack API, for example ``$ cs listVirtualMachines state=Running``.
You can pass credentials and the endpoint of your cloud as module arguments, however in most cases it is a far less work to store your credentials in the cloudstack.ini file.
The ENV variables support ``CLOUDSTACK_*`` as written in the documentation of the library ``cs``, like ``CLOUDSTACK_TIMEOUT``, ``CLOUDSTACK_METHOD``, and so on. has been implemented into Ansible. It is even possible to have some incomplete config in your cloudstack.ini:
Since Ansible 2.3 it is possible to use environment variables for domain (``CLOUDSTACK_DOMAIN``), account (``CLOUDSTACK_ACCOUNT``), project (``CLOUDSTACK_PROJECT``), VPC (``CLOUDSTACK_VPC``) and zone (``CLOUDSTACK_ZONE``). This simplifies the tasks by not repeating the arguments for every tasks.
The following should give you some ideas how to use the modules to provision VMs to the cloud. As always, there isn't only one way to do it. But as always: keep it simple for the beginning is always a good start.
Our CloudStack cloud has an advanced networking setup, we would like to provision web servers, which get a static NAT and open firewall ports 80 and 443. Further we provision database servers, to which we do not give any access to. For accessing the VMs by SSH we use a SSH jump host.
The configure the jumphost, web servers and database servers, we use ``group_vars``. The ``group_vars`` directory contains 4 files for configuration of the groups: cloud-vm, jumphost, webserver and db-server. The cloud-vm is there for specifying the defaults of our cloud infrastructure.
The web servers should get a ``Small`` offering as we would scale them horizontally, which is also our default offering. We also ensure the known web ports are opened for the world.
In the above play we defined 3 tasks and use the group ``cloud-vm`` as target to handle all VMs in the cloud but instead SSH to these VMs, we use ``delegate_to: localhost`` to execute the API calls locally from our workstation.
In the first task, we ensure we have a running VM created with the Debian template. If the VM is already created but stopped, it would just start it. If you like to change the offering on an existing VM, you must add ``force: yes`` to the task, which would stop the VM, change the offering and start the VM again.
..Note:: For some modules, for example ``cs_sshkeypair`` you usually want this to be executed only once, not for every VM. Therefore you would make a separate play for it targeting localhost. You find an example in the use cases below.
A basic networking CloudStack setup is slightly different: Every VM gets a public IP directly assigned and security groups are used for access restriction policy.
In the first play we setup the security groups, in the second play the VMs will created be assigned to these groups. Further you see, that we assign the public IP returned from the modules to the host inventory. This is needed as we do not know the IPs we will get in advance. In a next step you would configure the DNS servers with these IPs for accessing the VMs with their DNS name.