Initialize project.

There are three ways to setup the project.

1. Pure config based
2. Inline your python script
3. Combination of the two above

Pure

This type of initializatioon means you store everythink in your config.yaml file, and nornir is told where to look for this file, and the rest depends on the configs contents.

from nornir import InitNornir
nr = InitNornir(config_file="config.yaml")

Inline

This type allows you to specify details for the core and the inventory configuration.

from nornir import InitNornir
nr = InitNornir(
    core={"num_workers": 100},
    inventory={
        "plugin": "nornir.plugins.inventory.simple.SimpleInventory",
        "options": {
            "host_file": "inventory/hosts.yaml",
            "group_file": "inventory/groups.yaml",
            "default_file": "inventory/defaults.yaml"
        }
    }
)

When you create your nr object with the dry_run=True argument, it will just simulate the changes, and wont apply them.

Combination

Depending on your current situation it can come in handy when you combine the two concepts above.

from nornir import InitNornir
nr = InitNornir(core={"num_workers": 50}, config_file="config.yaml")

hosts.yaml

An example for the hosts file, this file contains details as to how the connection is made agains the host, which group does the host belong to, etc… THe data section comes in handy when you are filtering your hosts.

---
host1.dc1:
    hostname: centosa
    port: 22
    username: nornir
    password: nornir
    platform: linux
    groups:
        - dc1
    data:
        site: home
        role: host
        type: host

groups.yaml

Groups allow you to organize your hosts based on functionality and other criterias. You are able to specify global section to apply information globally to the groups.

---
global:
    data:
        company: r3ap3rpy
dc1:
    data:
        location: frankfurt

defaults.yaml

This file allows you to have information applied to your groups, hosts etc… this is used when on other levels the referenced information cannotbe found.

---
data:
    market: devops

Now that we have laid the fundations we can go and practice some commands