En este documento se describe la función Easy Virtual Network (EVN), diseñada para proporcionar un mecanismo de virtualización fácil de configurar en las redes de las instalaciones. Utiliza tecnologías actuales, como Virtual Routing and Forwarding Lite (VRF-Lite) y encapsulación dot1q, y no introduce ningún protocolo nuevo.
No hay requisitos específicos para este documento.
La información que contiene este documento se basa en estas versiones de software y hardware.
La información que contiene este documento se creó a partir de los dispositivos en un ambiente de laboratorio específico. Todos los dispositivos que se utilizan en este documento se pusieron en funcionamiento con una configuración verificada (predeterminada). Si tiene una red en vivo, asegúrese de entender el posible impacto de cualquier comando.
A continuación se muestra una descripción general de la función EVN:

Utilice la información que se describe en esta sección para configurar la función EVN.
Esta configuración de red se utiliza para ilustrar la configuración de EVN y los comandos show:

Estas son algunas notas importantes sobre esta configuración:
Complete estos pasos para configurar la función EVN:
vrf definition [name]
vnet tag [2-4094]
!
address-family ipv4|ipv6
exit-address-family
!
vrf definition CUST-A
vnet tag 100
!
address-family ipv4
exit-address-family
vrf definition CUST-B
vnet tag 200
!
address-family ipv4
exit-address-family
CORE-1#show vnet counters
Maximum number of VNETs supported: 32
Current number of VNETs configured: 2
Current number of VNET trunk interfaces: 2
Current number of VNET subinterfaces: 4
Current number of VNET forwarding interfaces: 6
CORE-1#
interface GigabitEthernetx/x
vnet trunk
ip address x.x.x.x y.y.y.y
...
CORE-1#show run | s Ethernet0/0
interface Ethernet0/0
vnet trunk
ip address 192.168.1.1 255.255.255.252
!
CORE-1#
CORE-1#show derived-config | s Ethernet0/0
interface Ethernet0/0
vnet trunk
ip address 192.168.1.1 255.255.255.252
Interface Ethernet0/0.100
description Subinterface for VNET CUST-A
encapsulation dot1Q 100
vrf forwarding CUST-A
ip address 192.168.1.1 255.255.255.252
interface Ethernet0/0.200
description Subinterface for VNET CUST-B
encapsulation dot1Q 200
vrf forwarding CUST-B
ip address 192.168.1.1 255.255.255.252
CORE-1#
interface GigabitEthernet x/x.y
vrf forwarding [name]
ip address x.x.x.x y.y.y.y
...
interface Ethernet2/0
vrf forwarding CUST-A
ip address 10.1.2.1 255.255.255.0
!
interface Ethernet3/0
vrf forwarding CUST-B
ip address 10.2.2.1 255.255.255.0
!
interface Ethernet4/0
vrf forwarding COM
ip address 100.1.1.1 255.255.255.0
router ospf x vrf [name]
network x.x.x.x y.y.y.y area x
...
CORE-1#show run | s router os
router ospf 1 vrf CUST-A
network 10.1.1.0 0.0.0.255 area 0
network 192.168.1.0 0.0.0.255 area 0
router ospf 2 vrf CUST-B
network 10.2.1.0 0.0.0.255 area 0
network 192.168.1.0 0.0.0.255 area 0
CORE-1#
CORE-1#routing-context vrf CUST-A
CORE-1%CUST-A#
CORE-1%CUST-A#show ip protocols
*** IP Routing is NSF aware ***
Routing Protocol is "ospf 1"
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 192.168.1.13
It is an area border router
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
10.1.1.0 0.0.0.255 area 0
192.168.1.0 0.0.0.255 area 0
Routing Information Sources:
Gateway Distance Last Update
192.168.1.9 110 1d00h
192.168.1.14 110 1d00h
Distance: (default is 110)
CORE-1%CUST-A#
CORE-1%CUST-A#show ip os neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.1.14 1 FULL/DR 00:00:30 192.168.1.14 Ethernet1/0.100
192.168.1.5 1 FULL/BDR 00:00:37 192.168.1.2 Ethernet0/0.100
10.1.1.2 1 FULL/BDR 00:00:33 10.1.1.2 Ethernet2/0
CORE-1%CUST-A#
CORE-1%CUST-A#show ip route 10.1.2.0
Routing Table: CUST-A
Routing entry for 10.1.2.0/24
Known via "ospf 1", distance 110, metric 30, type intra area
Last update from 192.168.1.2 on Ethernet0/0.100, 1d00h ago
Routing Descriptor Blocks:
* 192.168.1.14, from 192.168.1.9, 1d00h ago, via Ethernet1/0.100
Route metric is 30, traffic share count is 1
192.168.1.2, from 192.168.1.9, 1d00h ago, via Ethernet0/0.100
Route metric is 30, traffic share count is 1
CORE-1%CUST-A#
CORE-1%CUST-A#routing-context vrf CUST-B
CORE-1%CUST-B#
CORE-1%CUST-B#show ip route 10.2.2.0
Routing Table: CUST-B
Routing entry for 10.2.2.0/24
Known via "ospf 2", distance 110, metric 30, type intra area
Last update from 192.168.1.2 on Ethernet0/0.200, 1d00h ago
Routing Descriptor Blocks:
* 192.168.1.14, from 192.168.1.6, 1d00h ago, via Ethernet1/0.200
Route metric is 30, traffic share count is 1
192.168.1.2, from 192.168.1.6, 1d00h ago, via Ethernet0/0.200
Route metric is 30, traffic share count is 1
CORE-1%CUST-B#
CORE-1%CUST-B#exit
CORE-1#
CORE-1#
vrf definition VRF-X
address-family ipv4|ipv6
route-replicate from vrf VRF-Y unicast|multicast
[route-origin] [route-map [name]]
vrf definition CUST-A
address-family ipv4
route-replicate from vrf COM unicast connected
!
vrf definition CUST-B
address-family ipv4
route-replicate from vrf COM unicast connected
!
vrf definition COM
address-family ipv4
route-replicate from vrf CUST-A unicast ospf 1 route-map USERS
route-replicate from vrf CUST-B unicast ospf 2 route-map USERS
!
route-map USERS permit 10
match ip address prefix-list USER-SUBNETS
!
ip prefix-list USER-SUBNETS seq 5 permit 10.0.0.0/8 le 32
CORE-4#show ip route vrf CUST-A
Routing Table: COM
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area,* - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP
a - application route
+ - replicated route, % - next hop override
...
10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks
O 10.1.1.0/24 [110/30] via 192.168.1.10, 3d19h, Ethernet1/0.100
[110/30] via 192.168.1.5, 3d19h, Ethernet0/0.100
100.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C + 100.1.1.0/24 is directly connected (COM), Ethernet4/0
CORE-4#show ip route vrf CUST-B
... 10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks
O 10.2.1.0/24 [110/30] via 192.168.1.10, 1d00h, Ethernet1/0.200
[110/30] via 192.168.1.5, 1d00h, Ethernet0/0.200
100.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C + 100.1.1.0/24 is directly connected (COM), Ethernet4/0
CORE-4#show ip route vrf COM
...
10.0.0.0/24 is subnetted, 2 subnets
O + 10.1.1.0 [110/30] via 192.168.1.10 (CUST-A), 3d19h, Ethernet1/0.100
[110/30] via 192.168.1.5 (CUST-A), 3d19h, Ethernet0/0.100
O + 10.2.1.0 [110/30] via 192.168.1.10 (CUST-B), 1d00h, Ethernet1/0.200
[110/30] via 192.168.1.5 (CUST-B), 1d00h, Ethernet0/0.200
100.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 100.1.1.0/24 is directly connected, Ethernet4/0
vrf definition VRF-X
address-family ipv4
route-replicate from vrf >global unicast|multicast [route-origin]
[route-map [name]]
exit-address-family
!
exit
!
global-address-family ipv4 unicast
route-replicate from vrf [vrf-name] unicast|multicast [route-origin]
[route-map [name]]
router ospf x vrf VRF-X
redistribute vrf VRF-Y [route-origin] [route-map [name]]
router ospf 1 vrf CUST-A
redistribute vrf COM connected subnets route-map CON-2-OSPF
!
route-map CON-2-OSPF permit 10
match ip address prefix-list COM
!
ip prefix-list COM seq 5 permit 100.1.1.0/24
CE-A-1#ping 100.1.1.100
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 100.1.1.100, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms
CE-A-1#
CE-B-1#ping 100.1.1.100
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 100.1.1.100, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms
CE-B-1#
Esta sección proporciona información que puede utilizar para ajustar el troncal VNET.
De forma predeterminada, todos los VRF configurados con una etiqueta VNET están permitidos en todos los troncales VNET. Una lista de trunk le permite especificar la lista de VRFs autorizados en el trunk de VNET:
vrf list [list-name]
member [vrf-name]
!
interface GigabitEthernetx/x
vnet trunk list [list-name]
Como ejemplo, CORE-1 está ajustado para el VRF CUST-B en el troncal VNET entre CORE-1 y CORE-2:
vrf list TEST
member CUST-A
!
interface ethernet0/0
vnet trunk list TEST
Como se muestra, el peering OSPF para VRF CUST-B a través del trunk deja de funcionar:
%OSPF-5-ADJCHG: Process 2, Nbr 192.168.1.2 on Ethernet0/0.200 from FULL to DOWN,
Neighbor Down: Interface down or detached
Se quita la subinterfaz para VRF CUST-B:
CORE-1#show derived-config | b Ethernet0/0
interface Ethernet0/0
vnet trunk list TEST
ip address 192.168.1.1 255.255.255.252
!
interface Ethernet0/0.100
description Subinterface for VNET CUST-A
encapsulation dot1Q 100
vrf forwarding CUST-A
ip address 192.168.1.1 255.255.255.252
!
De forma predeterminada, las subinterfaces dot1q heredan los parámetros de la interfaz física para que las subinterfaces de todos los VRF tengan los mismos atributos (como el costo y la autenticación). Puede ajustar los parámetros troncales por etiqueta VNET:
interface GigaEthernetx/x
vnet trunk
vnet name VRF-X
ip ospf cost 100
vnet name VRF-Y
ip ospf cost 15
Puede ajustar estos parámetros:
CORE-1(config-if-vnet)#?
Interface VNET instance override configuration commands:
bandwidth Set bandwidth informational parameter
default Set a command to its defaults
delay Specify interface throughput delay
exit-if-vnet Exit from VNET submode
ip Interface VNET submode Internet Protocol config commands
no Negate a command or set its defaults
vnet Configure protocol-independent VNET interface options
CORE-1(config-if-vnet)#
CORE-1(config-if-vnet)#ip ?
authentication authentication subcommands
bandwidth-percent Set EIGRP bandwidth limit
dampening-change Percent interface metric must change to cause update
dampening-interval Time in seconds to check interface metrics
hello-interval Configures EIGRP-IPv4 hello interval
hold-time Configures EIGRP-IPv4 hold time
igmp IGMP interface commands
mfib Interface Specific MFIB Control
multicast IP multicast interface commands
next-hop-self Configures EIGRP-IPv4 next-hop-self
ospf OSPF interface commands
pim PIM interface commands
split-horizon Perform split horizon
summary-address Perform address summarization
verify Enable per packet validation
CORE-1(config-if-vnet)#ip
En este ejemplo, se cambia el costo OSPF por VRF para CORE-1, de modo que la trayectoria CORE-2 se utiliza para CUST-A y la trayectoria CORE-3 para CUST-B (el costo predeterminado es 10
interface Ethernet0/0
vnet name CUST-A
ip ospf cost 8
!
vnet name CUST-B
ip ospf cost 12
!
CORE-1#show ip route vrf CUST-A 10.1.2.0
Routing Table: CUST-A
Routing entry for 10.1.2.0/24
Known via "ospf 1", distance 110, metric 28, type intra area
Last update from 192.168.1.2 on Ethernet0/0.100, 00:05:42 ago
Routing Descriptor Blocks:
* 192.168.1.2, from 192.168.1.9, 00:05:42 ago, via Ethernet0/0.100
Route metric is 28, traffic share count is 1
CORE-1#
CORE-1#show ip route vrf CUST-B 10.2.2.0
Routing Table: CUST-B
Routing entry for 10.2.2.0/24
Known via "ospf 2", distance 110, metric 30, type intra area
Last update from 192.168.1.14 on Ethernet1/0.200, 00:07:03 ago
Routing Descriptor Blocks:
* 192.168.1.14, from 192.168.1.6, 1d18h ago, via Ethernet1/0.200
Route metric is 30, traffic share count is 1
CORE-1#
De forma predeterminada, la etiqueta VNET que se define en la definición VRF se utiliza para todos los troncos. Sin embargo, puede utilizar una etiqueta VNET diferente por tronco.
En este ejemplo se describe un escenario en el que se está conectado a un dispositivo no compatible con EVN y se utiliza VRF-Lite con un troncal manual, y la etiqueta VNET global es utilizada por otra VLAN:

Con esta configuración, la etiqueta VNET que se utiliza en el trunk entre CORE-1 y CORE-2 para CUST-A se cambia de 100 a 101:
interface Ethernet0/0
vnet name CUST-A
vnet tag 101
Después de que este cambio ocurre en CORE-1, se crea una nueva subinterfaz:
CORE-1#show derived-config | b Ethernet0/0
interface Ethernet0/0
vnet trunk
ip address 192.168.1.1 255.255.255.252
!
interface Ethernet0/0.101
description Subinterface for VNET CUST-A
encapsulation dot1Q 101
vrf forwarding CUST-A
ip address 192.168.1.1 255.255.255.252
!
interface Ethernet0/0.200
description Subinterface for VNET CUST-B
encapsulation dot1Q 200
vrf forwarding CUST-B
ip address 192.168.1.1 255.255.255.252
Si este cambio ocurre solamente en un extremo, la conectividad se pierde en el VRF asociado y el OSPF se desactiva:
%OSPF-5-ADJCHG: Process 1, Nbr 192.168.1.5 on Ethernet0/0.101 from FULL to DOWN,
Neighbor Down: Dead timer expired
Una vez que se utiliza la misma etiqueta VNET en CORE-2, se restaura la conectividad y se utiliza la etiqueta dot1q 101 en ese trunk mientras que 100 se sigue usando en el trunk CORE-1 a CORE-3:
%OSPF-5-ADJCHG: Process 1, Nbr 192.168.1.5 on Ethernet0/0.101 from LOADING to
FULL, Loading Done
Actualmente, no hay un procedimiento de verificación disponible para esta configuración.
Actualmente, no hay información específica de troubleshooting disponible para esta configuración.
| Revisión | Fecha de publicación | Comentarios |
|---|---|---|
1.0 |
04-Aug-2014
|
Versión inicial |