A declarative framework for building CLI-based network configurations
Netdefine attempts to address pain points found when moving from hand-crafted CLI files to CLI templates and abstracted variable data.
Using Netdefine, engineers can build device templates from a self-service repository of shared components. These components are referenced by Features, which contain the required data for each template. Each device template then becomes a list of Features that describes the configuration of the device.
Netdefine tracks the state of each file in your configuration repository by computing a hash of the file bytes, when a file is changed, netdefine plan can be ran to track which devices require updates due to a change in an underlying feature or component.
This is an example of a basic directory structure for a Netdefine project.
The components directory stores all resubale CLI templates as J2 files. The Features directory contains the features written per-device, each feature references a component and provides the required data to produce the template.
The templates directory contains template files which link features together to produce a device configuration.
├── components
│ ├── example-cisco_ios_baseline.j2
│ ├── example-cisco_ios_bgp.j2
│ ├── example-cisco_ios_l3_interfaces.j2
│ ├── example-cisco_ios_ospf.j2
│ └── example-cisco_ios_static_routes.j2
├── configs
│ └── first_change-config-example-cisco_ios_router_1.yml.txt
├── features
│ ├── example_router_1_baseline.yml
│ ├── example_router_1_bgp.yml
│ ├── example_router_1_interfaces.yml
│ ├── example_router_1_ospf.yml
│ └── example_router_1_static_routes.yml
├── state.json
└── templates
└── example-cisco_ios_router_1.yml
By default Netdefine will create a state.json file in your project root directory and output configutation files to the configs directory.
This package is in its very early stages and is not pushed to PyPi, to install netdefine, clone this repository and run the setup file after creating a virtual environment.
python netdefine/src/setup.py develop
From there, you will have access to the netdefine command. Change into the examples/globomantics directory and run netdefine plan
Netdefine will then create a state file to track the project folder.
(venv) daltonbell@Daltons-MacBook-Pro globomantics % netdefine plan
State file not found, building state...
state built successfully
The state has not changed since the last apply
to generate configurations, use the apply command and specify a change
(venv) daltonbell@Daltons-MacBook-Pro globomantics % netdefine apply first_change
apply success for change first_change
to validate a change without updating state (check j2 and yaml syntax and references) use the dry_run flag
(venv) daltonbell@Daltons-MacBook-Pro globomantics % netdefine apply first_change --dry_run
apply success for change first_change
to view the templates produced by change in the console, utilize the --display flag
(venv) daltonbell@Daltons-MacBook-Pro globomantics % netdefine apply first_change \
> --dry_run \
> --display
apply success for change first_change
Template:
example-cisco_ios_router_1.yml
Config:
hostname example-router-1
ip domain-name globomantics.net
ip name-server 10.254.0.1
ip ssh version 2
username cisco secret cisco
line vty 0 15
login local
banner motd ^
******************************************
THIS IS A TEST CONFIGURATION
******************************************
!
router ospf 100
passive-interface loop0
!
router bgp 65000
neighbor 10.255.255.2 remote-as 65000
network 10.100.100.0 mask 255.255.255.0
!
ip route 10.100.100.0 255.255.255.0 10.255.255.3
!
interface loop0
ip address 10.255.255.1 255.255.255.255
ip ospf 100 area 0
no shutdown
!
interface G0
ip address 10.0.0.1 255.255.255.252
ip ospf 100 area 0
no shutdown
!
interface G1
ip address 10.0.0.5 255.255.255.252
ip ospf 100 area 0
no shutdown
!
To target a specific template utilize the --target flag
(venv) daltonbell@Daltons-MacBook-Pro globomantics % netdefine apply first_change \
--dry_run \
--display \
--target=example-cisco_ios_router_1.yml
apply success for change first_change
Template:
example-cisco_ios_router_1.yml
Config:
hostname example-router-1
ip domain-name globomantics.net
ip name-server 10.254.0.1
ip ssh version 2
username cisco secret cisco
line vty 0 15
login local
banner motd ^
******************************************
THIS IS A TEST CONFIGURATION
******************************************
!
router ospf 100
passive-interface loop0
!
router bgp 65000
neighbor 10.255.255.2 remote-as 65000
network 10.100.100.0 mask 255.255.255.0
!
ip route 10.100.100.0 255.255.255.0 10.255.255.3
!
interface loop0
ip address 10.255.255.1 255.255.255.255
ip ospf 100 area 0
no shutdown
!
interface G0
ip address 10.0.0.1 255.255.255.252
ip ospf 100 area 0
no shutdown
!
interface G1
ip address 10.0.0.5 255.255.255.252
ip ospf 100 area 0
no shutdown
!
Install dev requirements using pip install - requirements.dev.txt
Run the test suite with pytest
(venv) daltonbell@Daltons-MacBook-Pro net_define % pytest
====================================================================== test session starts ======================================================================
platform darwin -- Python 3.9.5, pytest-6.2.4, py-1.10.0, pluggy-0.13.1
rootdir: /Users/daltonbell/github-repos/net_define
plugins: cov-2.12.1
collected 12 items
netdefine/tests/test_config_template.py . [ 8%]
netdefine/tests/test_netdefine.py ........... [100%]
====================================================================== 12 passed in 0.22s =======================================================================
(venv) daltonbell@Daltons-MacBook-Pro net_define %