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Router and switch discovery

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Router and switch discovery

Discovery identifies and classifies information about network routers and switches.

Network routers and switches often have very similar capabilities. It is very common for some switches known as Layer 3 switches to have IP routing. Larger routers with optional modules might accept switching modules. Because of these overlaps and the resulting ambiguity of a particular device's classification, Discovery collects the same data for both routers and switches, if it is available in any given device. For details on how Discovery collects data about connections between network devices and other components, see Layer 2 discovery.
Warning: DO NOT switch from probes to patterns if you are already running Discovery with probes, and your CMDB is already populated. If you do so, it is possible that the pattern Discovery process does not synchronize on the same values that the probe Discovery process does. This could result in duplicate CIs in your CMDB.

Prerequisites for server and network device discovery

  • The server or network device needs to have IP Address information.
  • The system property glide.discovery.L3_mapping is set to true to discover routers and switches.
  • The router or Layer 3 switch that provides the IP Address needs to have been successfully discovered with populated Exit Interface Routing Rules.

System properties

You can configure many aspects of Discovery to work according to your personal preferences. The following properties apply to network routers and switches. To view the properties, navigate to Discovery Definition > Properties unless indicated otherwise.
Property Description
glide.discovery.L3_mapping Provides a logical mapping of the TCP/IP layer for network gears. This is not Layer 2 mapping,
  • Type: string
  • Default value: true
  • Location: System Property [sys_properties] table
glide.discovery.max_concurrent_invocations_per_schedule Sets a maximum number of scheduled invocations of the same Discovery schedule. It prevents a backlog of scheduled runs if Discovery does not finish before the next invocation is scheduled to run. The value is an integer that represents the max number of automated invocations of the same schedule that may proceed at one time. If the limit has been reached, subsequent scheduled invocations are canceled. A value of 0 or any negative number disables this property.
  • Type: integer
  • Default value: 3
  • Location: Discovery Definition > Properties

Credentials

Discovery explores many kinds of devices, such as switches, routers, and printers, using the SNMP protocol. SNMP Community Credentials do not include a user name, just a password, which is the community string. The default read-only community string for many SNMP devices is public, and Discovery will try that automatically. SNMPv3 credentials require a user name and a key, depending on the protocol selected. Enter the appropriate SNMP credentials if they differ from the public community string.

Note: SSH is not supported for routers and switches, but is supported for load balancers.

Classifier, pattern, and probes

Classifiers Trigger probes Pattern
Standard Network Router

Standard Network Switch

  • Horizontal Pattern: launches patterns
  • SNMP-Routing^
  • DNS*
  • SNMP-Identity*
  • SNMP-Switch-Vlan*
  • SNMP-Switching*
  • SNMP - Network - ArpTable* (Standard Network Switch only)
Network Router

Network Switch

*For new instances, these probes are inactive on the classifier. Discovery uses patterns for discovery.

^This probe remains active by default for the Standard Network Router classifier, even when Discovery uses pattern discovery.

To use patterns, verify that the correct pattern is specified in the horizontal pattern probe on the classifier. See Add the Horizontal Pattern probe to a classifier for instructions.

Discovering stacked switches

The Network Switch shared library supports stacked switches. The CI table for this is IP Switch [cmdb_ci_ip_switch]. Multiple switches in the stack are identified by the master’s IP address. Each member of the stack is identified by a combination of elements, including the master IP address, a name associated with the switch, and the stack mode. The relationship is created between a master and all of its slaves.

Router and switch data

Table name Label/Field name Source
cmdb_ci

Serial Number

serial_number

SNMP, various MIBs
cmdb_ci

Start Date (only when target is a host)

start_date

SNMP, RFC1213 MIB
cmdb_ci

Manufacturer

manufacturer

SNMP, RFC1213 MIB
cmdb_ci

Model ID

model id

SNMP, RFC1213 MIB
cmdb_ci_ip_router

Name

name

cmdb_ci_ip_router

Model ID

model ID

SNMP, RFC1213 MIB
cmdb_ci_ip_router

Manufacturer

manufacturer

SNMP, RFC1213 MIB
cmdb_ci_ip_router

Serial Number

serial_number

SNMP, various MIBs
cmdb_ci_ip_router

IP Address

ip_address

SNMP, IP MIB
cmdb_ci_ip_router

Description

short_description

cmdb_ci_ip_router

Can route IP

can_route

SNMP, IP MIB, BGP MIB
cmdb_ci_ip_router

Can switch IP

can_switch

SNMP, dot1dBridge MIB
cmdb_ci_ip_switch

Name

name

cmdb_ci_ip_switch

Model ID

model ID

SNMP, RFC1213 MIB
cmdb_ci_ip_switch

Manufacturer

manufacturer

SNMP, RFC1213 MIB
cmdb_ci_ip_switch

Serial Number

serial_number

SNMP, various MIBs
cmdb_ci_ip_switch

IP Address

ip_address

SNMP, IP MIB
cmdb_ci_ip_switch

Description

short_description

cmdb_ci_ip_switch

Can route IP

can_route

SNMP, IP MIB, BGP MIB
cmdb_ci_ip_switch

Ports

ports

SNMP, dot1dBridge MIB
cmdb_ci_ip_switch

Can switch IP

can_switch

SNMP, dot1dBridge MIB
cmdb_ci_ip_switch

Can partition VLANs

can_partitionvlans

SNMP, dot1dBridge MIB
cmdb_ci_ip_switch

Stack

stack

SNMP, entPhysicalTable
cmdb_ci_ip_switch

Stack Mode

stack_mode

SNMP, entPhysicalTable
cmdb_ci_netgear

Can route IP

can_route

SNMP, IP MIB, BGP MIB
cmdb_ci_netgear

Can switch IP

can_switch

SNMP, dot1dBridge MIB
cmdb_ci_netgear

Can partition VLANs

cdscy_router_interface

SNMP, dot1dBridge MIB
cmdb_ci_netgear

Can Hub

can_hub

SNMP, IP MIB
cmdb_ci_network_adapter

IP Address

ip_address

SNMP, IP MIB
cmdb_ci_network_adapter

MAC Address

mac_address

SNMP, IF MIB
discovery_device_neighbors

Neighbor Address

neighbor_address

ciscoCdpMIB, lldpMIB
discovery_device_neighbors

Neighbor ID

neighbor_ID

ciscoCdpMIB, lldpMIB
discovery_device_neighbors

Neighbor Interface

neighbor_interface

ciscoCdpMIB, lldpMIB
discovery_device_neighbors

Neighbor Source

neighbor_source

ciscoCdpMIB, lldpMIB
discovery_device_neighbors

Origin Interface

origin_interface

ciscoCdpMIB, lldpMIB
discovery_net_arp_table

IP Address

IP_address

SNMP, IP MIB
discovery_net_arp_table

MAC Address

mac_address

SNMP, IP MIB
discovery_switch_bridge_port_table

Interface Index

interface_index

SNMP, dot1dBridge MIB
discovery_switch_bridge_port_table

Port

port

SNMP, dot1dBridge MIB
discovery_switch_fwd_table

MAC Address

mac_address

SNMP, dot1dBridge MIB
discovery_switch_fwd_table

Port

port

SNMP, dot1dBridge MIB
discovery_switch_fwd_table

Status

status

SNMP, dot1dBridge MIB
discovery_switch_fwd_table

VLAN ID

vlan_id

SNMP, dot1dBridge MIB
discovery_switch_spanning_tree_table

Designated Bridge MAC

designated_bridge_mac

SNMP, dot1dBridge MIB
discovery_switch_spanning_tree_table

Designated Root

designated_root

SNMP, dot1dBridge MIB
discovery_switch_spanning_tree_table

Port

port

SNMP, dot1dBridge MIB
discovery_switch_spanning_tree_table

Port Enable

port_enable

SNMP, dot1dBridge MIB
discovery_switch_spanning_tree_table

Port State

port_state

SNMP, dot1dBridge MIB
dscy_router_interface

Name

name

SNMP, IP MIB
dscy_router_interface

Type

type

SNMP, IP MIB
dscy_router_interface

Number

number

SNMP, IP MIB
dscy_router_interface

IP Address

ip_address

SNMP, IP MIB
dscy_router_interface

MAC Address

mac_address

SNMP, IP MIB
dscy_route_interface

Destination Network

dest_ip_network

SNMP, IP MIB
dscy_route_interface

Type

type

SNMP, IP MIB
dscy_route_next_hop

Destination Network

dest_ip_network

SNMP, IP MIB
dscy_route_next_hop

Type

type

SNMP, IP MIB
dscy_route_next_hop

Next Hop

next_hop_ip_address

SNMP, IP MIB
dscy_switchport

Type

type

SNMP, dot1dBridge MIB
dscy_switchport

Status

status

SNMP, dot1dBridge MIB
dscy_switchport

MAC Address

mac_address

SNMP, dot1dBridge MIB
dscy_switchport

Port Number

port_number

SNMP, dot1dBridge MIB
dscy_switchport

Interface Name

interface_name

SNMP, dot1dBridge MIB
dscy_switchport

Interface Number

interface_number

SNMP, dot1dBridge MIB
dscy_swtch_fwd_rule

MAC Address

mac_address

SNMP, dot1dBridge MIB
dscy_swtch_fwd_rule

MAC Manufacturer

mac_mfr

SNMP, dot1dBridge MIB
dscy_swtch_fwd_rule

Status

status

SNMP, dot1dBridge MIB
dscy_swtch_fwd_rule

IP address

ip_address

SNMP, dot1dBridge MIB
dscy_swtch_fwd_rule

Netmask

netmask

SNMP, dot1dBridge MIB
dscy_swtch_partition

Base IP Address

base_ip_address

SNMP, dot1dBridge MIB
dscy_swtch_partition

Base MAC Address

base_mac_address

SNMP, dot1dBridge MIB
dscy_swtch_partition

Base Netmask

base_netmask

SNMP, dot1dBridge MIB
dscy_swtch_partition

Type

type

SNMP, dot1dBridge MIB
dscy_swtch_partition

Transparent

transparent

SNMP, dot1dBridge MIB
dscy_swtch_partition

Source Route

sourceroute

SNMP, dot1dBridge MIB
dscy_swtch_partition

Name

name

SNMP, dot1dBridge MIB
dscy_swtch_partition

Status

status

SNMP, dot1dBridge MIB
dscy_swtch_partition

Interface Number

interface_number

SNMP, dot1dBridge MIB
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