explorer

Documentation

Overview

Package explorer provides facilities to explorer a network by connecting to a root node via a user/password and issuing CDP commands and then logging into its neighbors in parallel. This mostly just tries to Go version the Python script, with enhancements (like this will be way faster in a large network due to concurrency).

Note1: There really should be multiple explorers here. I'd probably start with SNMP. If that failed I might try device login with a user/pass/ssh key list. Enterprise network engineers have a bad tendancy to leave SNMP set to "public" or something easily guessable so they can run solarwinds or nagios easily. Yes, SNMP is terrible, but it can provide structured data for these old routers you can't export JSON from or do streaming telemetry.

Note2: CDP or LLDP could be used.

Note3: Routing protocols can give you enough information to detect neighbors. While not giving you the discovery that CDP/LLDP can, you can then just use that info to query the neighborts (OSPF/ISIS/...)

Note4: Not that I've dealt with pure switches in a while, but if your ARP table shows something, then you have a device there. If there is a link light, something has a mac address at least in a table. Using the OID you can get an idea of what is hanging off there even if you don't know what it is.

Note5: I'm sure this doesn't deal with a bunch of various interface options. And I no longer do network automation, so I don't have a bunch of devices to try this on. Basically, this is a REALLY junior effort. Just as a mental exercise while I didn't want to work on other things I should.

Index

• type List
  • func (l *List) List(n *network.Node) []*network.Node
• type LoginDeny
• type Network
  • func New(root string, conf config.Config) (*Network, error)
  • func (e *Network) Explore(ctx context.Context) (Results, error)
• type Results

Types

type List

type List struct {
	// contains filtered or unexported fields
}

List provides a method for walking the network.Node tree and returning a list of all Nodes without falling into a recursive loop.

func (*List) List

func (l *List) List(n *network.Node) []*network.Node

List turns the tree into a slice.

type LoginDeny

type LoginDeny struct {
	// IP is the IP of the node.
	IP net.IP
	// Err is the error we got.
	Err error
}

LoginDeny is used to log nodes we could not connect to.

type Network

type Network struct {
	// contains filtered or unexported fields
}

Network is used to explorer the network

func New

func New(root string, conf config.Config) (*Network, error)

New is the constructor for Network.

func (*Network) Explore

func (e *Network) Explore(ctx context.Context) (Results, error)

type Results

type Results struct {
	NetworkMap  *network.Node
	LoginDeny   []LoginDeny
	ParseErrors []error
}