Configurae Devices

SSH needs to be enabled and an appropriate username and password present. We are going to use GNS3 to emulate cisco IOS routers.

conf ter
line vty 0 4
transport input ssh
login local

username nornir password nornir
enable secret nornir

hostname c2681/c3745
ip domain-name r3ap3rpy.com


crypto key generate rsa
2048

ip ssh version 2


int fa0/0
ip address 192.168.56.100/111 255.255.255.0
no shut

Now you should be able to test the ssh connnection. You may have a situation that you need to add extra arguments for the ssh connection to work.

ssh -oKexAlgorithms=+diffie-hellman-group1-sha1 -c aes256-cbc nornir@192.168.56.100

Add them to hosts file

Let’s add the routers into our hosts file.

host2.home:
    hostname: 192.168.220.10
    port: 22
    username: nornir
    password: nornir
    platform: ios
    groups:
        - dc1
    data:
        site: home
        role: cisco
        type: router
    connection_options:
        napalm:
            extras:
                optional_args:
                    secret: nornir
        netmiko:
          extras:
              secret: nornir

host2.home:
    hostname: 192.168.220.11
    port: 22
    username: nornir
    password: nornir
    platform: ios
    groups:
        - dc1
    data:
        site: home
        role: cisco
        type: router
    connection_options:
        napalm:
            extras:
                optional_args:
                    secret: nornir
        netmiko:
          extras:
              secret: nornir

As you can see this is a bit different from the host before, and we have an extra connection option which is the secret password.

Run stuff against them

Now we can query some facts form our device.

from nornir import InitNornir
from nornir.plugins.functions.text import print_result
from nornir.plugins.tasks import networking

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

routers = nr.filter(site="home", role="cisco")
result = routers.run(task=networking.napalm_get,getters=["facts"])

print_result(result)

We can retrieve the running configuration aswell.

from nornir import InitNornir
from nornir.plugins.functions.text import print_result
from nornir.plugins.tasks import networking

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

routers = nr.filter(site="home", role="cisco")

result = routers.run(task=networking.napalm_get,getters=["config"],retrieve="all")
print_result(result)

We can perform remote pings aswell.

from nornir import InitNornir
from nornir.plugins.functions.text import print_result
from nornir.plugins.tasks import networking

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

routers = nr.filter(site="home", role="cisco")


result = routers.run(task=networking.napalm_ping,source='192.168.220.10',dest='192.168.220.1')
print_result(result)

We can modify the configuration aswell.

from nornir import InitNornir
from nornir.plugins.functions.text import print_result
from nornir.plugins.tasks import networking

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

routers = nr.filter(site="home", role="cisco")


result = routers.run(task=networking.netmiko_send_config,config_commands=['ip ssh version 2'])
print_result(result)