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Contents
- Configuring Easy Virtual Network
- Finding Feature Information
- Prerequisites for Configuring EVN
- How to Configure EVN
- Configuring an Easy Virtual Network Trunk Interface
- Enabling Only a Subset of VRFs over a Trunk Interface
- Configuring an EVN Edge Interface
- What to Do Next
- Verifying EVN Configurations
- Configuration Examples for Configuring EVN
- Example: Virtual Networks Using OSPF with network Commands
- Example: Virtual Networks Using OSPF with ip ospf vnet area Command
- Example: Command Inheritance and Virtual Network Interface Mode Override in an EIGRP Environment
- Example: Command Inheritance and Virtual Network Interface Mode Override in a Multicast Environment
- Example: EVN Using IP Multicast
- Additional References
- Feature Information for Configuring Easy Virtual Network
Configuring Easy Virtual Network
Easy Virtual Network (EVN) is an IP-based virtualization technology that provides end-to-end virtualization of the network. You can use a single IP infrastructure to provide separate virtual networks whose traffic paths remain isolated from each other. Configure Easy Virtual Network to configure two or more virtual IP networks.
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the Feature Information Table at the end of this document.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Prerequisites for Configuring EVN
- Implementing EVN in your network requires that you have a single IP infrastructure that you want to use to create two or more virtual networks. You want path isolation for the traffic on the different virtual networks.
- You should understand the concepts in the Overview of Easy Virtual Network module.
- We recommend you draw your network topology, indicating which interfaces on each router belong to which EVNs. The diagram will facilitate tracking which interfaces you are configuring as edge interfaces and which interfaces you are configuring as trunk interfaces.
How to Configure EVN
- Configuring an Easy Virtual Network Trunk Interface
- Enabling Only a Subset of VRFs over a Trunk Interface
- Configuring an EVN Edge Interface
- Verifying EVN Configurations
Configuring an Easy Virtual Network Trunk Interface
Perform this task to configure an EVN trunk interface, which connects routers to provide the core to transport traffic for multiple virtual networks. Traffic carried over a trunk interface is tagged. This task illustrates how to configure a trunk interface with a base VRF and two named VRFs: VRF red and VRF blue.
DETAILED STEPS
Enabling Only a Subset of VRFs over a Trunk Interface
The prior task, Configuring an Easy Virtual Network Trunk Interface, shows how to configure a trunk interface with two VRFs. By default, the trunk interfaces on a router can carry traffic for each VRF defined by the vrf definition command. However, you might want to enable only a subset of VRFs over a trunk interface, which is done by creating a VRF list. A maximum of 32 VRF lists can exist on a router. Perform the following task to create a VRF list. This task presumes that the VRF has already been configured.
DETAILED STEPS
Configuring an EVN Edge Interface
Perform this task to configure an edge interface, which connects a user device to a virtual network. Traffic carried over an edge interface is untagged. The edge interface determines which virtual network the received traffic belongs to. Each edge interface is mapped to only one virtual network.
DETAILED STEPS
What to Do Next
After you have configured an edge interface and a trunk interface, refer to your network diagram, and log on to a different router. If it is has an edge interface, configure that interface. If it has a trunk interface, configure that interface with the appropriate VRFs. Continue configuring each of the routers and interfaces that belong to each VRF.
Configure other protocol features you want running in your VRFs. See the appropriate IP Routing configuration guide.
Verifying EVN Configurations
Perform any of the following steps in this task to verify your configuration. Because a virtual network is a VRF, all the existing VRF show commands are supported for virtual networks. If a router has a mix of VRFs and virtual networks, the various show vrf commands will include both VRFs and virtual networks in the output.
DETAILED STEPS
Command or Action | Purpose | |
---|---|---|
Step 1 |
enable
Example: Router> enable |
Enables privileged EXEC mode.
|
Step 2 |
show
vnet
tag
Example: Router# show vnet tag |
(Optional) Displays where each tag has been configured or used. |
Step 3 |
show
running-config
[vrf | vnet][vrf-name] Example: Router# show running-config vrf green |
(Optional) Displays the VRFs in the running configuration, displays interfaces in VRFs, and displays protocol configurations for Multi-VRF. |
Step 4 |
show
vrf
list
[vrf-list-name] Example: Router# show vrf list |
(Optional) Displays information about VRF lists, such as VRFs on each list. |
Step 5 |
show
{vrf | vnet} [ipv4 | ipv6] [interface | brief| detail| lock] [vrf-name] Example: Router# show vnet detail |
(Optional) Displays information about the VRFs. |
Step 6 |
show
{vrf | vnet} counters Example: Router# show vnet counters |
(Optional) Displays information such as the number of VRFs or virtual networks supported and configured. |
Configuration Examples for Configuring EVN
- Example: Virtual Networks Using OSPF with network Commands
- Example: Virtual Networks Using OSPF with ip ospf vnet area Command
- Example: Command Inheritance and Virtual Network Interface Mode Override in an EIGRP Environment
- Example: Command Inheritance and Virtual Network Interface Mode Override in a Multicast Environment
- Example: EVN Using IP Multicast
Example: Virtual Networks Using OSPF with network Commands
In this example, network commands associate a shared VRF interface with a base VRF and two named VRFs, red and blue. There are three OSPF instances because each VRF needs its own OSPF instance. OSPF 1 has no VRF, so it is vnet global.
vrf definition red vnet tag 100 address-family ipv4 exit-address-family ! vrf definition blue vnet tag 200 address-family ipv4 exit-address-family ! interface gigabitethernet 0/0/0 ip address 10.0.0.1 255.255.255.0 vnet trunk vnet name red ip ospf cost 100 ! router ospf 1 log-adjacency-changes detail network 10.0.0.0 255.255.255.0 area 0 router ospf 2 vrf red log-adjacency-changes network 10.0.0.0 255.255.255.0 area 0 router ospf 3 vrf blue log-adjacency-changes network 10.0.0.0 255.255.255.0 area 2
Example: Virtual Networks Using OSPF with ip ospf vnet area Command
This example differs from the prior example regarding the association between OSPF instances and a particular interface. In this example, OSPF is running on all of the virtual networks of a trunk interface. The ip ospf vnet area command associates the GigabitEthernet 0/0/0 interface with the three OSPF instances.
vrf definition red vnet tag 100 address-family ipv4 exit-address-family ! vrf definition blue vnet tag 200 address-family ipv4 exit-address-family ! interface gigabitethernet 0/0/0 ip address 10.0.0.1 255.255.255.0 vnet trunk ip ospf vnet area 0 vnet name red ip ospf cost 100 vnet name blue ip ospf 3 area 2 ! router ospf 1 log-adjacency-changes detail router ospf 2 vrf red log-adjacency-changes router ospf 3 vrf blue log-adjacency-changes
Example: Command Inheritance and Virtual Network Interface Mode Override in an EIGRP Environment
Suppose a GigabitEthernet interface is configured with various EIGRP commands:
interface gigabitethernet0/0/0 vnet trunk ip address 1.1.1.1 255.255.255.0 ip authentication mode eigrp 1 md5 ip authentication key-chain eigrp 1 x ip bandwidth-percent eigrp 1 3 ip dampening-change eigrp 1 30 ip hello-interval eigrp 1 6 ip hold-time eigrp 1 18 no ip next-hop-self eigrp 1 no ip split-horizon eigrp 1 ip summary-address eigrp 1 1.0.0.0 255.0.0.0 end
Because a trunk is configured, a VRF subinterface is automatically created and the commands on the main interface are inherited by the VRF subinterface (g0/0/0.3, where the number 3 is the tag number from vnet tag 3 .)
R1# show running-config vrf red
Building configuration...
Current configuration : 1072 bytes
vrf definition red
vnet tag 3
!
address-family ipv4
exit-address-family
!
If you display that hidden subinterface with the show derived-config command, you'll see that all of the commands entered on GigabitEthernet 0/0/0 have been inherited by GigabitEthernet 0/0/0.3:
R1# show derived-config interface gigabitethernet0/0/0.3
Building configuration...
Derived configuration : 478 bytes
!
interface GigabitEthernet0/0/0.3
description Subinterface for VNET red
vrf forwarding red
encapsulation dot1Q 3
ip address 1.1.1.1 255.255.255.0
ip authentication mode eigrp 1 md5
ip authentication key-chain eigrp 1 x
ip bandwidth-percent eigrp 1 3
ip dampening-change eigrp 1 30
ip hello-interval eigrp 1 6
ip hold-time eigrp 1 18
no ip next-hop-self eigrp 1
no ip split-horizon eigrp 1
ip summary-address eigrp 1 1.0.0.0 255.0.0.0
end
You can override those commands by using virtual network interface mode (under the vnet name command). For example:
R1(config)# interface gigabitethernet0/0/0 R1(config-if)# vnet name red R1(config-if-vnet)# no ip authentication mode eigrp 1 md5 ! disable authen for e0/0.3 only R1(config-if-vnet)# ip authentication key-chain eigrp 1 y ! different key-chain R1(config-if-vnet)# ip band eigrp 1 99 ! higher bandwidth-percent R1(config-if-vnet)# no ip dampening-change eigrp 1 ! disable dampening-change R1(config-if-vnet)# ip hello eigrp 1 7 R1(config-if-vnet)# ip hold eigrp 1 21 R1(config-if-vnet)# ip next-hop-self eigrp 1 ! enable next-hop-self for e0/0.3 R1(config-if-vnet)# ip split-horizon eigrp 1 ! enable split-horizon R1(config-if-vnet)# no ip summary-address eigrp 1 1.0.0.0 255.0.0.0 ! do not summarize on e0/0.3
R1(config-if-vnet)# do show running-config interface gigabitethernet0/0/0
Building configuration...
Current configuration : 731 bytes
!
interface GigabitEthernet0/0/0
vnet trunk
ip address 1.1.1.1 255.255.255.0
ip authentication mode eigrp 1 md5
ip authentication key-chain eigrp 1 x
ip bandwidth-percent eigrp 1 3
ip dampening-change eigrp 1 30
ip hello-interval eigrp 1 6
ip hold-time eigrp 1 18
no ip next-hop-self eigrp 1
no ip split-horizon eigrp 1
ip summary-address eigrp 1 1.0.0.0 255.0.0.0
vnet name red
ip split-horizon eigrp 1
no ip summary-address eigrp 1 1.0.0.0 255.0.0.0
no ip authentication mode eigrp 1 md5
ip authentication key-chain eigrp 1 y
ip bandwidth-percent eigrp 1 99
no ip dampening-change eigrp 1
ip hello-interval eigrp 1 7
ip hold-time eigrp 1 21
ip next-hop-self eigrp 1
!
end
Notice that g0/0.3 is now using the override settings:
R1(config-if-vnet)# do show derived-config interface g0/0.3
Building configuration...
Derived configuration : 479 bytes
!
interface GigabitEthernet0/0/0.3
description Subinterface for VNET red
vrf forwarding red
encapsulation dot1Q 3
ip address 1.1.1.1 255.255.255.0
no ip authentication mode eigrp 1 md5
ip authentication key-chain eigrp 1 y
ip bandwidth-percent eigrp 1 99
no ip dampening-change eigrp 1
ip hello-interval eigrp 1 7
ip hold-time eigrp 1 21
ip next-hop-self eigrp 1
ip split-horizon eigrp 1
no ip summary-address eigrp 1 1.0.0.0 255.0.0.0
end
Commands entered in vnet name submode are sticky. That is, when you enter a command in vnet name submode, it will nvgen, regardless of whether it is set to the same value as the default value. For example, the default hello value is 5. When the ip hello eigrp command is entered in vnet name submode, it will nvgen; it does not do that in any other mode.
R1(config-if)# interface gigabitethernet0/0/2 R1(config-if)# vnet trunk R1(config-if)# ip bandwidth-percent eigrp 1 50 <---<< this will NOT nvgen R1(config-if)# ip hello eigrp 1 5 <---<< this will NOT nvgen R1(config-if)# no ip authentication mode eigrp 1 md5 <---<< this will NOT nvgen R1(config-if)# vnet name red R1(config-if-vnet)# ip bandwidth-percent eigrp 1 50 <---<< this will nvgen R1(config-if-vnet)# ip hello eigrp 1 5 <---<< this will nvgen R1(config-if-vnet)# no ip authentication mode eigrp 1 md5 <---<< this will nvgen R1(config-if-vnet)# do show running-config interface gigabitethernet0/0/2 Building configuration... Current configuration : 104 bytes ! interface GigabitEthernet0/0/2 vnet trunk no ip address vnet name red ip bandwidth-percent eigrp 1 50 ip hello-interval eigrp 1 5 no ip authentication mode eigrp 1 md5 !
Because of this sticky factor, to remove a configuration entry in vnet name submode, you typically must use the default form of that command. Some commands can also be removed using the no form; it depends on the command. Some commands use the no form to disable the command instead, such as the authentication and summary-address commands.
R1(config-if-vnet)# default ip authentication mode eigrp 1 md5 R1(config-if-vnet)# no ip bandwidth-percent eigrp 1 R1(config-if-vnet)# no ip hello eigrp 1 R1(config-if-vnet)# do show running-config interface g0/2 Building configuration... Current configuration : 138 bytes ! interface GigabitEthernet0/0/2 vnet trunk no ip address vnet name red ! end
Example: Command Inheritance and Virtual Network Interface Mode Override in a Multicast Environment
The following example illustrates command inheritance and virtual network interface mode override in a multicast network. A trunk interface leverages the fact that configuration requirements from different VRFs will be similar over the same trunk interface. Eligible commands configured on the trunk interface are inherited by all VRFs running over the same interface.
In this example, IP multicast (PIM sparse mode) is configured on the trunk interface, which has several VRFs:
vrf definition red vnet tag 13 ! address-family ipv4 exit-address-family ! ip multicast-routing ip multicast-routing vrf red interface GigabitEthernet0/1/0 vnet trunk ip address 125.1.15.18 255.255.255.0 ip pim sparse-mode
The user decides that he does not want IP multicast configured for VRF red on GigabitEthernet 0/1/0, so he uses the virtual network interface mode override. IP Multicast is disabled for VRF red only. The no ip pim command disables all modes of PIM, including sparse mode, dense mode, and sparse-dense mode, for VRF red.
interface GigabitEthernet0/1/0 vnet trunk ip address 125.1.15.18 255.255.255.0 ip pim sparse-mode vnet name red no ip pim
Example: EVN Using IP Multicast
The following example configures PIM sparse mode and leverages Anycast RP for RP redundancy. (In this example, only one VRF is configured.)
Enable multicast routing globally and on each L3 interface. The black text indicates the group of commands configuring the global table; the red text indicates the group of commands configuring VRF red.
ip multicast-routing interface GigabitEthernet 1/1/1 description GigabitEthernet to core (Global) GLOBAL TABLE ip pim sparse-mode vrf definition red vnet tag 100 ! address-family ipv4 exit-address-family ! ip multicast-routing vrf red VRF RED ! interface gigabitethernet1/1/1.100 description GigabitEthernet to core (VRF red) vrf forwarding red ip pim sparse-mode
Configure the RP in the VRF using Anycast RP.
interface loopback0 description Anycast RP Global ip address 10.122.5.200 255.255.255.255 ip pim sparse-mode ! interface loopback1 description MDSP Peering interface ip address 10.122.5.250 255.255.255.255 GLOBAL TABLE ip pim sparse-mode ! ip msdp peer 10.122.5.251 connect-source loopback 1 ip msdp originator-id loopback 1 ip pim rp-address 10.122.5.200 access-list 10 permit 239.0.0.0 0.255.255.255 ! ! interface loopback 10 description Anycast RP VRF Red vrf forwarding red ip address 10.122.15.200 255.255.255.255 ip pim sparse-mode interface loopback 11 description MSDP Peering interface VRF red VRF RED vrf forwarding red ip address 10.122.15.250 255.255.255.255 ip pim sparse-mode ! ip msdp vrf red peer 10.122.15.251 connect-source loopback 11 ip msdp vrf red originator-id loopback 11 ! ip pim vrf red rp-address 10.122.15.200 access-list 11 permit 239.192.0.0 0.0.255.255
Additional References
Related Documents
Related Topic |
Document Title |
---|---|
Cisco IOS commands |
|
Easy Virtual Network commands |
|
Information about Easy Virtual Network |
"Overview of Easy Virtual Networks" module in the Easy Virtual Network Configuration Guide. |
Easy Virtual Network shared services and route replication |
"Configuring Easy Virtual Network Shared Services" module in the Easy Virtual Network Configuration Guide. |
Easy Virtual Network management and troubleshooting |
"Easy Virtual Network Management and Troubleshooting" module in the Easy Virtual Network Configuration Guide. |
MIBs
MIB |
MIBs Link |
---|---|
Any MIB that gives VRF information will continue to work with Easy Virtual Network. VRF-Independent MIBs report information on every VRF in a system: |
To locate and download MIBs for selected platforms, Cisco software releases, and feature sets, use Cisco MIB Locator found at the following URL: |
Technical Assistance
Description |
Link |
---|---|
The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password. |
Feature Information for Configuring Easy Virtual Network
The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Table 1 | Feature Information for Configuring Easy Virtual Network |
Feature Name |
Releases |
Feature Information |
---|---|---|
EVN VNET Trunk |
Cisco IOS XE Release 3.2S 15.0(1)SY 15.1(1)SG Cisco IOS XE Release 3.3SG |
This module describes how to configure virtual IP networks. An EVN is an IP-based virtualization technology that provides end-to-end virtualization of the network. You can use a single IP infrastructure to provide separate virtual networks whose traffic paths remain isolated from each other. The following commands were modified: The following commands were introduced: |
EVN OSPF |
Cisco IOS XE Release 3.2S 15.0(1)SY 15.1(1)SG Cisco IOS XE Release 3.3SG |
EVN OSPF provides Easy Virtual Network support for OSPF. The following commands were modified:
The following command was introduced: |
EVN EIGRP |
Cisco IOS XE Release 3.2S 15.0(1)SY 15.1(1)SG Cisco IOS XE Release 3.3SG |
EVN EIGRP provides Easy Virtual Network support for EIGRP. The following commands were modified: |
EVN Multicast |
Cisco IOS XE Release 3.2S 15.0(1)SY 15.1(1)SG Cisco IOS XE Release 3.3SG |
EVN Multicast provides Easy Virtual Network support for IP Multicast. |
Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S. and other countries. To view a list of Cisco trademarks, go to this URL: www.cisco.com/go/trademarks. Third-party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (1110R)
Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental.