CMLNetKit

What is CMLNetKit?

CMLNetKit is an application for automatic pre-configuration of nodes in Cisco Modeling Labs 2.x

This version has been tested with Python 3.10 and CML2.5.

In the Cisco VIRL, the most valuable feature is AutoNetKit. It creates the initial configuration of simulated devices, including the interface IP address, the loopback interfaces addressing, routing protocols, and many more. This feature pretty much does not exist in Cisco Modeling Labs 2.0 (aka. Cisco VIRL2), requiring a manual configuration of every IP address of every interface in the lab topology. The CMLNetKit brings some of the AutoNetKit features back to CML2.0

You need to run the CMLNetKit before starting the lab. CMLNetKit won't amend running lab nodes configurations.

Features

The following features are currently available:

• Reading and writing the lab configuration from API
• Changing all External Connection objects types to Bridge
• Addressing Loopback interface
• Addressing management interfaces
• Addressing directly connected interfaces between two nodes

CMLNetKit does not modify the provided source lab topology; instead, it creates a new lab using the same lab title.

Management interfaces

The dedicated management interfaces are not present on all node types. In this application, the management interfaces are statically defined as per the below table. If you request CMLNetKit to assign IP addresses to the management interfaces, it will treat the following interfaces as management. It would be best to connect these interfaces to a dedicated out-of-band network via External Connector node.

Node type	Management interface
iosv	GigabitEthernet0/0
csr1000v	GigabitEthernet1
iosxrv	MgmtEth0/0/CPU0/0
iosxrv9000	MgmtEth0/RP0/CPU0/0
nxosv	mgmt0
nxosv9000	mgmt0
iosvl2	GigabitEthernet0/0
asav	Management0/0

Initial configuration changes

Before you start, you need to add nodes to the topology and connect them. Then generate the initial configuration of your lab nodes via CML2 GUI. To do that, open the CML2 GUI, select your lab and click anywhere on the background. Then select Design tab and press the Build Initial Bootstrap Configurations button.

If you update the topology by adding the new nodes, you need to generate initial configurations for them before running the CMLNetKit again.

The CMLNetKit won't amend the interface configuration if IP addresses are already present. How to install CMLNetKit? =========================

Please follow the steps described below to install the CMLNetKit.

Pre-requisites

CMLNetKit requires Python versions 3.5+. The OS should not matter. It has been tested on Python version 3.7.7 on Linux and MacOS.

The required Python libraries are defined in requirements.txt. It is also recommended to have git client installed on the host. Alternatively, you can download the repository package from GitHub project site.

It is required to run CMLNetKet from the host that is allowed to access the CML2 API. If you can access the CML2 GUI, you can also use the CMLNetKit from this host.

Installation

Download the CMLNetKit repository

$ git clone https://github.com/WojciechowskiPiotr/CMLNetKit
$ cd CMLNetKit

Install required python libraries

$ pip install -r requirements.txt

Usage

The minimum required parameter is the hostname or IP address of the CML2 server provided as -H value. If no username or password is provided, the default of virl2/virl2 is used. To disable the SSL verification, always add --no-ssl-verification to any command you run.

The following options are required or optional. You can always display help using the -h parameter.

usage: cmlnetkit.py [-h] [-H HOST] [-l LAB_ID] [--list-labs] [--list-ips]
                    [-P PORT] [-u USERNAME] [-p PASSWORD]
                    [--no-ssl-verification] [--dry-run] [-b]
                    [--lo-subnet LOOPBACK_SUBNET]
                    [--mgmt-range MGMT_IP_LOW MGMT_IP_HIGH]
                    [--peer-subnet PEER_SUBNET]
                    [--mgmt-netmask MGMT_NETMASK | --mgmt-prefixlen MGMT_PREFIXLEN]

optional arguments:
  -h, --help            show this help message and exit

Connection options:
  -H HOST, --host HOST  CML2.0 host address
  -l LAB_ID, --lab LAB_ID
                        Lab ID
  --list-labs           List the ID of existing labs
  --list-ips            List the IP addresses configured on L3 links
  -P PORT, --port PORT  CML 2.0 API port (default 443)
  -u USERNAME, --username USERNAME
                        CML 2.0 API username (default "virl2")
  -p PASSWORD, --password PASSWORD
                        CML 2.0 API password (default "virl2")
  --no-ssl-verification
                        Disable the SSL certification verification on the CML2
                        server
  --dry-run             Don't apply any changes to CML2 server.

Configuration changes:
  -b                    Changing all "External Connection" objects
                        configuration to "Bridge"
  --lo-subnet LOOPBACK_SUBNET
                        Subnet for the Loopback ip addresses assignment, must
                        be provided in format as subnet/mask. If mask not
                        provided default mask for subnet is used.If none
                        provided the default 10.0.0.0/24 is used. Loopback
                        addresses are always /32
  --mgmt-range MGMT_IP_LOW MGMT_IP_HIGH
                        Contiguous range of IP addresses must be provided. As
                        argument values provide first and last IP address of
                        the range
  --peer-subnet PEER_SUBNET
                        Subnet for the ip addresses assignment for direct
                        connections betweend devices,must be provided in
                        format as subnet/mask. If mask not provided the /24 is
                        used.Direct connections betweend devices are addressed
                        with /30 mask
  --mgmt-netmask MGMT_NETMASK
                        Subnet mask that needs to be assigned to management
                        interfaces IP addresses on devices. Mask must be
                        provided in standard netmask notation 255.255.255.0 If
                        neither -mgmt-netmask nor -mgmt-prefixlen is provided
                        then /24 prefixlen (mask of 255.255.255.0) is
                        assigned.
  --mgmt-prefixlen MGMT_PREFIXLEN
                        Subnet mask that needs to be assigned to management
                        interfaces IP addresses on devices. Prefixlen must be
                        provided as integer between 0 and 32. If neither
                        -mgmt-netmask nor -mgmt-prefixlen is provided then /24
                        prefixlen (mask of 255.255.255.0) is assigned.

Usage examples

First, you need to list available labs on the CML2 server. In GUI, you see the lab's names, but in CMLNetKit, you need to provide the lab ID. To list all the available labs, use the --list-labs parameter.

cmlnetkit.py -H cml.server.address --list-labs

In the output, you will see all the available labs. The first column contains six characters long lab ID. Please provide it every time using -l as a reference to source lab you want to modify.

To change the "External Connection" objects configuration to "bridge".

cmlnetkit.py -H cml.server.address -l abc123 -b

If you want to amend addressing the Loopback interfaces, use the --lo-subnet parameter followed by the subnet you want to use for loopbacks. CMLNetKit will assign /32 addresses from this subnet for the Loopback interfaces of each node.

cmlnetkit.py -H cml.server.address -l abc123 --lo-subnet 10.0.0.0/24

To assign addresses to management interfaces, you need to provide two parameters: using the --mgmt-range specify the first and the last IP address of the continuous range that should be used for management interfaces, and then --mgmt-prefixlen to specify the subnet mask lengths that should be assigned. .. code:

cmlnetkit.py -H cml.server.address -labc123 --mgmt-range 172.16.16.2 172.16.16.25 --mgmt-prefixlen 24

To address interfaces the direct connections between the simulation devices, you need to provide a subnet for peer-to-peer connections. It will be subnetted into /30's subnet per each link.

cmlnetkit.py -H cml.server.address -l abc123 --peer-subnet 10.100.0.0/22

You can use the parameters altogether with SSL verification disabled to perform all operations at once

cmlnetkit.py -H cml.server.address -l abc123 --no-ssl-verification -lo --lo-subnet 10.0.0.0/24 -mgmt --mgmt-range 172.16.16.2 172.16.16.25 --mgmt-prefixlen 24 --peer-subnet 10.100.0.0/22

List IP addresses assigned to devices in initial configuration

cmlnetkit.py -H cml.server.address -l abc123 --list-ip

Support and requests

If you find a bug or want to request additional features, please open the Issue on the CMLNetKit GitHub project at https://github.com/WojciechowskiPiotr/CMLNetKit