Examples¶

This page provides a few simple examples on how to use the VIRL ² Client Library:

from virl2_client import ClientLibrary
client = ClientLibrary("https://192.168.1.1", "username", "password")
client.wait_for_lld_connected()

A custom SSL certificate bundle can be passed in ssl_verify:

client = ClientLibrary("https://192.168.1.1", "username", "password", ssl_verify="./cert.pem")

You can pass a certificate using the CA_BUNDLE environment variable as well.

If no username or password are given then the environment will be checked, looking for VIRL2_USER and VIRL2_PASS, respectively. Environment variables take precedence over those provided in arguments.

It’s also possible to pass the URL as an environment variable VIRL2_URL.

Disabling SSL certificate verification (not recommended):

client = ClientLibrary("https://192.168.1.1", "username", "password", ssl_verify=False)

Creating a lab with nodes and links¶

This creates a lab, adds two nodes, interfaces and a link between them:

lab = client.create_lab()

r1 = lab.create_node("r1", "iosv", 50, 100)
r1.config = "hostname router1"
r2 = lab.create_node("r2", "iosv", 50, 200)
r2.config = "hostname router2"

# create a link between r1 and r2
r1_i1 = r1.create_interface()
r2_i1 = r2.create_interface()
lab.create_link(r1_i1, r2_i1)

# alternatively, use this convenience function:
lab.connect_two_nodes(r1, r2)

# start the lab
lab.start()

# print nodes and interfaces states:
for node in lab.nodes():
    print(node, node.state, node.cpu_usage)
    for interface in node.interfaces():
        print(interface, interface.readpackets, interface.writepackets)

lab.stop()

lab.wipe()

lab.remove_node(r2)

lab.remove()

Stopping all the labs¶

This snippet loops over all labs and stops them:

for lab in client_library.all_labs():
    lab.stop()

Getting all lab names¶

Get a list of all the lab names the user owns:

all_labs_names = [lab.name for lab in client_library.all_labs()]

Stopping all labs of a User¶

The following code loops over all labs the user owns, stops the lab, wipes the lab and then removes the lab from the controller:

lab_list = client_library.get_lab_list()
for lab_id in lab_list:
    lab = client_library.join_existing_lab(lab_id)
    lab.stop()
    lab.wipe()
    client_library.remove_lab(lab_id)

Uploading an image disk file¶

This shows how to upload a local disk file to the controller. It can then be used with to create a image definition for a given node type:

filename = "/Users/username/Desktop/vios-adventerprisek9-m.spa.158-3.m2.qcow2"
client_library.definitions.upload_image_file(filename, rename="iosv-test.qcow2")

Using the Client Library with Netmiko¶

The following example shows how the VIRL2 client library can be combined with Netmiko.

The code shows how to identify a XRv node in a specific lab and how to create crypto keys which require special handling as the creation is done in exec mode and is interactive:

import getpass
import netmiko

from virl2_client import ClientLibrary

LAB_USERNAME = 'cisco'
LAB_PASSWORD = 'cisco'
VIRL_CONTROLLER = 'virl2-controller'
VIRL_USERNAME = input('username: ')
VIRL_PASSWORD = getpass.getpass('password: ')

client = ClientLibrary(VIRL_CONTROLLER,
                       VIRL_USERNAME,
                       VIRL_PASSWORD,
                       ssl_verify=False)
client.wait_for_lld_connected()

# this assumes that there's exactly one lab with this title
our_lab = client.find_labs_by_title('my_lab')[0]
xr_node = our_lab.get_node_by_label('pe2')

# open the Netmiko connection via the terminal server
# (SSH to the controller connects to the terminal server)
c = netmiko.ConnectHandler(device_type='terminal_server',
                           host=VIRL_CONTROLLER,
                           username=VIRL_USERNAME,
                           password=VIRL_PASSWORD)

# send CR, get a prompt on terminal server
c.write_channel('\r')

# open the connection to the console
c.write_channel(f'open /{our_lab.id}/{xr_node.id}/0\r')

# router login
# this makes an assumption that it's required to login
c.write_channel('\r')
c.write_channel(LAB_USERNAME + '\r')
c.write_channel(LAB_PASSWORD + '\r')

# switch to Cisco XR mode
netmiko.redispatch(c, device_type='cisco_xr')
c.find_prompt()

# get the list of interfaces
result = c.send_command('show ip int brief')
print(result)

# create the keys
result = c.send_command('crypto key generate rsa',
                        expect_string='How many bits in the modul us \[2048\]\: ')
print(result)

# send the key length
c.write_channel('2048\n')

# retrieve the result
result = c.send_command('show crypto key mypubkey rsa')
print(result)