autodiscovery device attributes discovery ports discovery cdp neighbours discovery layer 3 hosts...

AutoDiscovery

Device Attributes Discovery

Ports Discovery

CDP Neighbours Discovery

Layer 3 Hosts Discovery

Introduction• Reliable monitoring and efficient use depends on the accuracy

of the entered data that describe the network and the network devices.

• AutoDiscovery function aims: • Easing the initial database population• Updating - topology, new devices and relevant data

• Discovery on hop-by-hop basis• Better overview and control over the process• No retrieval of the entire network • Possibility of clear database organisation in the system

Location A

Location 1

Router 1

Location A3

Router B

Serial 0

Serial 1

Router A

Router C

Router D

Serial 1

Router A

Serial 0

Router A2

Router A1

Router A3

Router A3

•notesnotes……

PC1

PC2

PC3

PC4

PC5

M

M

Principles• AutoDiscovery functions are performed on the Device objects

or their Ports• Data is read and retrieved via SNMP • Result are shown in the Message panel• AutoDiscovery functions perform following actions:

• Attempts to find the discovered Devices in the database • Device already exists in the database -> update of the object

properties and Links• Device does not exist in the database -> Device is created in the

Discovered Folder, located underneath the Device on which the AutoDiscovery service was initialised.

• Links are being set to the discovered Devices/Ports, depending on the type of initialized AutoDiscovery function.

Device Attributes Discovery • Setting the Name information for every SNMP

enabled device• For Cisco Systems devices, finds serial

number and model information• Plans for the future…

• Deeper and intelligent analysis• Discovering type of the device and manufacturer• Discovering device attributes (type of hardware,

type of OS, memory and storage size…)

Ports Discovery• Discovers all network interfaces (ports) with following

attributes: • short and full name of the port• description of the port• bandwidth • SNMP ID

• Port objects are updated or created under the Device in the information system hierarchy and each Port is linked to the parent Device

• SNMP ID – index to member in OID list - the most important port attribute

• Optional selection of automatic PortDiscovery function on the Devices on daily basis

• Persistent interface indexes

CDP Neighbours Discovery • Based on CDP (Cisco Discovery Protocol)

• Discovering neighbour devices

• Creating the Links between Devices

• CDP offers the information about models of these devices, as well as connected ports

• The final result is creating Links between two Ports of neighbouring Devices, which represents the topological connection in this part of the computer network

• Cisco only up to now - waiting for the Link Layer Discovery Protocol (LLDP) and MIB…

Layer 3 Hosts Discovery • Started on routers (Layer 3 device) or router ports

• Discovers all IP address of end devices (hosts) on adhering local segments (sub-networks)

• Based on ARP table• NetIIS system gets the address range in the adhering sub-network.

This address range is pinged, in order to refresh the router’s ARP table, from where IP and MAC addresses of end devices are retrieved

• NetBIOS and DNS names are requested from host devices, which are set in the Device name

• A new object type Device is created within the Discovered Folder, which presents the local sub-network, under a name based on the IP address and length of the mask split with an under score (e.g. 10.1.2.0_24)

AutoDiscovery

Summary

Device Attributes Discovery

Ports Discovery

CDP Neighbours Discovery

Layer 3 Neighbours Discovery