Inventory

This sections describes the Ansible inventory of the Krake project. Ansible works against multiple infrastructure hosts. Hosts are configured in an inventory file hosts.yml which is a standard Ansible YAML inventory that uses multiple groups structure and a custom krake_inventory plugin (see auto plugin).

Inventory plugin

The krake_inventory custom plugin loads the JSON file defined by variable hosts_file and augments the host variables with dynamic variables (e.g. public and private IP addresses) depending on host. The location of JSON file which stores inferred information can be configured by specifying the hosts_file variable in the all group . If it is not specified it defaults to .etc/<inventory-filestem>.json.

Inventory structure

Krake inventory file hosts.yml uses Ansible multiple groups structure of inventory.

Global variables for all hosts are defined under the vars sub-section. This sub-section defines following:

keypair

OpenStack SSH key pair name of public ssh key which will be used for accessing the infrastructure to deploy hosts. Different keys could be defined directly for specific group or host.

key_file

SSH private key file path on local computer for corresponding keypair. If key_file is set to null, the default SSH identity (~/.ssh/id_rsa) will be used.

gateway

SSH jump host that is used to access the OpenStack instances. By default, no OpenStack server has a floating IP assigned except hosts in the gateways group. All other hosts use the gateway host variable to define a SSH jump host. Wireguard is also installed on the gateway, see Access through the gateway

authorized_keys - optional

List of additional authorized SSH keys, which can be used for accessing the hosts.

Each Krake infrastructure host is defined by corresponding host group sub-section in Krake inventory file. The default parameters for every host group are defined in the group_vars/ directory where the filename matches the group name. Krake inventory file defines following host groups and host variables:

gateways

SSH jump host that is used to access the OpenStack instances.

network

Inventory name of the network on which this SSH jump host should be deployed

vpn_cidr

VPN Classless Inter-Domain Routing definition (e.g. 10.9.0.0/24). This will define the wireguard network. Each peer on this network (the gateway and users or administrators of the deployment) will have a specific address on this network.

wireguard_peers

List of all wireguard peer for whom access should be granted on the gateway. Several peers can be added. A wireguard configuration file will be created for each peer.

name

The name of the peer. This string is used to differentiate the different peers from each other. It will also be given to the wireguard network interface. The value can be arbitrary, but should be unique per deployment, or over deployment if you plan on managing several ones with the same machine.

public_key

The wireguard public key of the peer.

IP

Set the IP that will be given to the current peer in the wireguard network. Each peer should be given a different IP to prevent conflicts. The IP can be chosen in the vpn_cidr network, as long as it is not the IP given to the gateway (which is the first in the network by default).

networks

Networks group define “virtual” hosts. These hosts exist purely for provisioning purpose. No machines are associated with them.

subnet_name

Subnet name

subnet_cidr

Subnet Classless Inter-Domain Routing definition (e.g. 192.168.0.0/24)

public_network

Public network type (e.g. shared-public-IPv4)

router_name

Router name

common_secgroup_name

Secure group name

central_idps

Central IdP host group used for keystone federation of Krake infrastructure.

network

Inventory name of the network on which this IdP should be deployed

devstacks

Devstack host group used for deployment of Krake devstack backends.

id

Unique DevStack ID. This ID is also used to define the IP network of the DevStack instance in the private network

network

Inventory name of the network on which this DevStack should be deployed

idp

Inventory name of the IdP that should be used for federation by this DevStack

prometheus

Inventory name of the Prometheus server that should be used for the monitoring of this DevStack backend

magnum_clusters

Magnum cluster host group used for deployment of magnum clusters on underlying devstack backend.

name

Magnum cluster name

devstack

Inventory name of underlying devstack backend which hosted the magnum cluster deployment

prometheus

Inventory name of the Prometheus server that should be used for the monitoring of this magnum cluster

use_keystone

Enables keystone deployment on this magnum cluster

minikube_clusters

Minikube cluster host group used for deployment of minikube clusters.

name

Minikube cluster name

network

Inventory name of the network on which this minikube cluster should be deployed

idp

Inventory name of the IdP that should be used for federation by this minikube

use_keystone

Enables keystone deployment on this minikube cluster

prometheus

Prometheus host group used for deployment of Prometheus monitoring server.

hostname

Prometheus VM host name

network

Inventory name of the network on which this minikube cluster should be deployed

krake_apps

Krake application host group used for deployment Krake infrastructure

hostname

Krake VM host name

network

Inventory name of the network on which this minikube cluster should be deployed