Network Configuration Analysis

Hyojoon Kim and Nick Feamster

School of Computer Science

Georgia Tech

Individual devices configured with low-level CLI

commands

Proprietary tools for devices from the same vendor

Each vendor has different syntax

How is the network configured?

Network Configuration is Hard!

Complex

Fragile & error-prone

Then again, availability of the network is critical

Current solutions are insufficient

RANCID

NCCM (Network Changes & Configuration

Management)

Configuration Statistics can Help…

Inform the operator about the status of their network

Provide better understanding of network configuration

Identify the problem area for possible improvements

Network configuration files at Georgia Tech

1,722 network devices (including virtual instances)

Collected daily (using RANCID)

Data set

Implementation

Analysis tool

Analysis package

Shell script extracts a set of configuration files

C program analyzes each configuration file

Preliminary Results

How many vendors and how many devices from each vendor?

How many devices of each type (e.g., switch, router, firewall)?

How many total lines of configuration?

How are the lines of configuration distributed across various tasks?

Routers

Firewalls

Switches

How Many Vendors?

How Many Devices of Each Type?

How Many Lines of Configuration?

How Much Config for Each Task?

Operational Tasks for Routers

Operational Tasks for Firewalls

Operational Tasks for Switches

The Problem Area

Questions in Ongoing Study

Which tasks are common?

What types of errors are most common?

How many devices are affected for specific tasks?

Is there a correlation between complexity & configuration?

Does configuration become more or less complex

over time?

What is the best way to reduce complexity?

We need your help!

Future Work

Need more configuration data to run & test our analysis tool

Our tool

A simple script running over configuration snapshots

Analyzes the configuration files, and derives statistics

Does not collected any sensitive data

Contact:

Hyojoon (Joon) Kim ( joonk@gatech.edu )

Nick Feamster ( feamster@cc.gatech.edu )