Nety 1.3.5

Parse, Audit, Query, Build, and Modify Cisco IOS-style configurations

Table of Contents

• Introduction: What is Nety?

• What if we don’t use Cisco?

• Docs

• Pre-requisites

• Installation and Downloads

• FAQ

• Other Resources

• Bug Tracker and Support

• Unit-Tests

• License and Copyright

• Author and Thanks

Introduction: What is Nety?

Nety is a Python library, which parses through Cisco IOS-style (and other vendor) configurations. It can:

• Audit existing router / switch / firewall / wlc configurations

• Retrieve portions of the configuration

• Modify existing configurations

• Build new configurations

The library examines an IOS-style config and breaks it into a set of linked parent / child relationships. You can perform complex queries about these relationships.

What if we don’t use Cisco?

Don’t let that stop you.

As of Nety 1.2.4, you can parse brace-delimited configurations into a Cisco IOS style (see Github Issue #17), which means that Nety understands these configurations:

• Juniper Networks Junos, and Screenos

• F5 Networks configurations

Nety also handles anything that has a Cisco IOS style of configuration, which includes:

• Cisco IOS, Cisco Nexus, Cisco IOS-XR, Cisco IOS-XE, Aironet OS, Cisco ASA, Cisco CatOS

• Arista EOS

• Brocade

• HP Switches

• Force 10 Switches

• Dell PowerConnect Switches

• Extreme Networks

• Enterasys

Docs

• You can find the HTML Docs online

• There is also a Nety Tutorial

Pre-requisites

Nety requires Python versions 3.5+ (We no longer support Python 2.x); the OS should not matter. If you want to run it under a Python virtualenv, it’s been heavily tested in that environment as well.

Installation and Downloads

The best way to get Nety is with setuptools or pip. If you already have setuptools, you can install as usual:

# Substitute whatever Nety version you like...
easy_install -U nety==1.3.0

Alternatively you can install into Python2.x with pip:

pip install --upgrade Nety

Use pip3 for Python3.x…

pip3 install --upgrade Nety

Otherwise download it from PyPi, extract it and run the setup.py script:

python setup.py install

If you’re interested in the source, you can always pull from the github repo:

• From github:

  git clone https://github.com/YtenSoftware/Nety.git

FAQ

1. QUESTION: I want to use Nety with Python3; is that safe? ANSWER: As long as you’re using Python 3.3 or higher, it’s safe. I test every release against Python 3.2+; however, Python 3.2 is currently exposed to a small bug for some configurations (see Github Issue #14).

2. QUESTION: Some of the code in the documentation looks different than what I’m used to seeing. Did you change something? ANSWER: Yes, starting around Nety v0.9.10 I introducted more methods directly on IOSConfigLine() objects; going forward, these methods are the preferred way to use Nety. Please start using the new methods shown in the example, since they’re faster, and you type much less code this way.

3. QUESTION: Nety saved me a lot of time, I want to give money. Do you have a donation link? ANSWER: I love getting emails like this; helping people get their jobs done is why I wrote the module. However, I’m not accepting donations.

4. QUESTION: Is there a way to use this module with perl? ANSWER: Yes, I do this myself. Install the python package as you normally would and import it into perl with Inline.pm and Inline::Python from CPAN.

5. QUESTION: When I use find_children("interface GigabitEthernet3/2"), I’m getting all interfaces beginning with 3/2, including 3/21, 3/22, 3/23 and 3/24. How can I limit my results? ANSWER: There are two ways… the simplest is to use the ‘exactmatch’ option… find_children("interface GigabitEthernet3/2", exactmatch=True). Another way is to utilize regex expansion that is native to many methods… find_children("interface GigabitEthernet3/2$")

Other Resources

• Dive into Python3 is a good way to learn Python

• Team CYMRU has a Secure IOS Template, which is especially useful for external-facing routers / switches

• Cisco’s Guide to hardening IOS devices

Bug Tracker and Support

• Please report any suggestions, bug reports, or annoyances with Nety through the github bug tracker.

• If you’re having problems with general python issues, consider searching for a solution on Stack Overflow. If you can’t find a solution for your problem or need more help, you can ask a question.

• If you’re having problems with your Cisco devices, you can open a case with Cisco TAC; if you prefer crowd-sourcing, you can ask on the Stack Exchange Network Engineering site.

Unit-Tests

Travis CI project tests Nety on Python versions 2.6 through 3.4, as well as a pypy JIT executable.

Click the image below for details; the current build status is:

License and Copyright

Nety is licensed GPLv3; 2016.

Author and Thanks

Nety was developed by Yten Software

Special thanks to mpenning for his great CiscoConfParse, Nety is a successor of it!