NorFab Inventory

NorFab comes with Simple Inventory Datastore (SID) hosted by broker.

Broker Inventory

TBD

Workers Inventory

To understand how Simple Inventory Datastore serves workers inventory it is good to know that each worker has a unique name to identify it.

With that in mind, the goal is to map inventory data to individual worker by its name.

For example, let's pretend that worker name is nornir-worker-1 and we have common.yaml and nornir-worker-1.yaml files with inventory data that we need to provide worker with.

To do the mapping between worker name and inventory files we can put this in NorFab inventory (inventory.yaml) file:

workers:
  nornir-*:
    - nornir/common.yaml  
  nornir-worker-1:
    - nornir/nornir-worker-1.yaml

Where files structure would look like this:

└───rootfolder
    │   inventory.yaml
    │
    └───nornir
            common.yaml
            nornir-worker-1.yaml

As you can see, inventory.yaml file contains workers section with a dictionary keyed by glob patterns to match against workers' names, once worker name matched by the pattern, all items in the list underneaths that pattern being loaded and recursively merged. As such, process continues until all patterns evaluated. Final output of the process is a combined inventory data of all the matched files.

The recursive logic of combining inventory data files is pretty straightforward - each next data file merged into the previous data file overriding the overlapping values.

The glob pattern matching logic allows be as specific as required and map specific files to individual workers or to map single data file to multiple workers or map multiple files to multiple workers, all combinations supported.

For example, we have a group of two workers with names netbox-wroker-1.1 and netbox-worker-1.2 and we want to map netbox_common.yaml to both of the workers, in that case NorFab inventory (inventory.yaml) file could have this content:

workers:
  netbox-worker-1.*:
    - nornir/netbox_common.yaml  

Where files structure would look like this:

└───rootfolder
    │   inventory.yaml
    │
    └───netbox
            netbox_common.yaml

Both workers will be served with netbox_common.yaml file content as an inventory data.

Workers Inventory Parameters

Workers inventory can contain these common parameters:

1. service - name of the service this worker belongs to
2. broker_endpoint - Broker URL to connect to

Sample worker base inventory:

service: nornir
broker_endpoint: "tcp://127.0.0.1:5555"

The rest of the inventory data is worker specific.

Topology Inventory

Topology section of NorFab inventory identifies the components that need to be started on the given node.