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ciscoconfparse2

Introduction: What is ciscoconfparse2?

Summary

ciscoconfparse2 is similar to an advanced grep and diff that handles multi-vendor network configuration files (such as those from Arista, Cisco, F5, Juniper, Palo Alto, etc); it is the next generation of ciscoconfparse, which was the primary development package from 2007 until 2023.

A ciscoconfparse2 example

Assume you have a bunch of interfaces in a configuration. How do you find which ones are shutdown?

One way is manually reading the whole Cisco IOS-XE configuration. Another option is ciscoconfparse2

>>> from ciscoconfparse2 import CiscoConfParse
>>>
>>> parse = CiscoConfParse('/path/to/config/file')
>>> intf_cmds = parse.find_parent_objects(['interface', 'shutdown'])
>>>
>>> shut_intf_names = [" ".join(cmd.split()[1:]) for cmd in intf_cmds]
>>>
>>> shut_intf_names
['GigabitEthernet1/5', 'TenGigabitEthernet2/2', 'TenGigabitEthernet2/3']
>>>

Another ciscoconfparse2 example

Assume you have this IOS-XR bgp configuration:

router bgp 65534
  bgp router-id 10.0.0.100
  address-family ipv4 unicast
  !
  neighbor 10.0.0.37
    remote-as 64000
    route-policy EBGP_IN in
    route-policy EBGP_OUT out
  !
  neighbor 10.0.0.1
    remote-as 65534
    update-source Loopback0
    route-policy MANGLE_IN in
    route-policy MANGLE_OUT out
      next-hop-self
  !
  neighbor 10.0.0.34
    remote-as 64000
    route-policy EBGP_IN in
    route-policy EBGP_OUT out

You can generate the list of EBGP peers pretty quickly with this script:

from ciscoconfparse2 import CiscoConfParse

parse = CiscoConfParse('/path/to/config/file')   # Or read directly from a list of strings

# Get all neighbor configuration branches
branches = parse.find_object_branches(('router bgp',
                                       'neighbor',
                                       'remote-as'))

# Get the local BGP ASN
bgp_cmd = branches[0][0]
local_asn = bgp_cmd.split()[-1]

# Find EBGP neighbors for any number of peers
for branch in branches:
    neighbor_addr = branch[1].split()[-1]
    remote_asn = branch[2].split()[-1]
    if local_asn != remote_asn:
        print("EBGP NEIGHBOR", neighbor_addr)

When you run that, you'll see:

$ python example.py
EBGP NEIGHBOR 10.0.0.37
EBGP NEIGHBOR 10.0.0.34
$

There is a lot more possible; see the tutorial.

CLI Tool

ciscoconfparse2 distributes a CLI tool that will diff and grep various network configuration or text files.

API Examples

The API examples are documented on the web

Why

ciscoconfparse2 is a Python library that helps you quickly search for questions like these in your router / switch / firewall / load-balancer / wireless text configurations:

What interfaces are shutdown?
Which interfaces are in trunk mode?
What address and subnet mask is assigned to each interface?
Which interfaces are missing a critical command?
Is this configuration missing a standard config line?

It can help you:

Audit existing router / switch / firewall / wlc configurations
Modify existing configurations
Build new configurations

Speaking generally, the library examines a text network config and breaks it into a set of linked parent / child relationships. You can perform complex queries about these relationships.

What changed in ciscoconfparse2?

In late 2023, I started a rewrite because ciscoconfparse is too large and has some defaults that I wish it didn't have. I froze ciscoconfparse PYPI releases at version 1.9.41; there will be no more ciscoconfparse PYPI releases.

What do you do? Upgrade to ciscoconfparse2!

Here's why, it:

Includes a handy CLI command (including greps for mac addresses and IPv4 / IPv6 subnets)
Streamlines the API towards a simpler user interface.
Removes legacy and flawed methods from the original (this could be a breaking change for old scripts).
Adds string methods to BaseCfgLine() objects
Defaults ignore_blank_lines=False (this could be a breaking change for old scripts).
Is better at handling multiple-child-level configurations (such as IOS XR and JunOS)
Can search for parents and children using an arbitrary list of ancestors
Adds the concept of change commits; this is a config-modification safety feature that ciscoconfparse lacks
Adds an auto_commit keyword, which defaults True
Documents much more of the API
Intentionally requires a different import statement to minimize confusion between the original and ciscoconfparse2
Vasly improves Cisco IOS diffs

Docs, Installation, and Dependencies

The latest copy of the docs are archived on the web

Installation and Downloads

Use pip for Python3.x... :
```
python -m pip install ciscoconfparse2
```

Dependencies

Pre-requisites

The ciscoconfparse2 python package requires Python versions 3.7+.

Type-hinting (work-in-progress) targets Python3.9+ due to the need for tuple[str, ...] hints.

What is the pythonic way of handling script credentials?

Never hard-code credentials
Use python-dotenv

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
Center for Internet Security Benchmarks (An email address, cookies, and javascript are required)

Are you releasing licensing besides GPLv3?

I will not. however, if it's truly a problem for your company, there are commercial solutions available (to include purchasing the project, or hiring me).

Bug Tracker and Support

Please report any suggestions, bug reports, or annoyances with a github bug report.
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 on Stack Overflow or reddit/r/Python.
If you're having problems with your Cisco devices, you can contact:

License and Copyright

ciscoconfparse2 is licensed GPLv3

The word "Cisco" is a registered trademark of Cisco Systems.

Author

ciscoconfparse2 was written by David Michael Pennington.