Configuring the Router Interface

To create Router Interfaces for the tunnel endpoints:

To configure the Router Interface on one of the tunnel end points:
1. Enter global configuration mode.
```
SLX# configure terminal
SLX (config)# 
```
2. Create the Router Interface. A Router Interface is a VE interface.
```
SLX (config)# interface Ve 20
SLX (conf-if-Ve-20)# 
```
3. To configure VRF support for this VE interface. Through this configuration, VRF is supported on the GRE IPv4 tunnel. Here the VRF is named red.
```
SLX (conf-if-Ve-20)# vrf forwarding red
SLX (conf-if-Ve-20)# 
```
4. Configure the OSPF for IPv4 traffic.
```
SLX (conf-if-Ve-20)# ip ospf area 1
SLX (conf-if-Ve-20)# 
```
  You can also configure ISIS and BGP protocols.
5. Configure the OSPF for IPv6 traffic.
```
SLX (conf-if-Ve-20)# ipv6 ospf area 1
SLX (conf-if-Ve-20)# 
```
  You can also configure ISIS and BGP protocols.
  
  Note
  
  When configuring OSPFv3 for IPv6, ensure no ACLs are applied on this VE. This limitation is applicable to SLX 9740 and Extreme 8820 devices only.
6. Configure the IPv4 address for the VE interface. This configuration enables the transmission of IPv4 traffic through the GRE Tunnel.
```
SLX (conf-if-Ve-20)# ip address 23.23.23.1/24
SLX (conf-if-Ve-20)# 
```
7. Configure the IPv6 address for the VE interface. This configuration enables the transmission of IPv6 traffic through the GRE Tunnel.
```
SLX (conf-if-Ve-20)# ipv6 address 2301:1::1:1/64 
SLX (conf-if-Ve-20)# 
```
8. Exit out the VE interface configuration.
```
SLX (conf-if-Ve-20)# exit
SLX (config)# 
```
To configure the Router Interface on the other tunnel end point:
1. Enter global configuration mode.
```
SLX# configure terminal
SLX (config)# 
```
2. Create the Router Interface. A Router Interface is a VE interface.
```
SLX (config)# interface Ve 22
SLX (conf-if-Ve-22)# 
```
3. To configure VRF support for this VE interface. Through this configuration, VRF is supported on the GRE IPv4 tunnel. Here the VRF is named red.
```
SLX (conf-if-Ve-22)# vrf forwarding red
SLX (conf-if-Ve-22)# 
```
4. Configure the OSPF area to consolidate traffic from a single network. This configures the OSPF area for IPv4 traffic.
```
SLX (conf-if-Ve-22)# ip ospf area 1
SLX (conf-if-Ve-22)# 
```
  You can also configure ISIS and BGP protocols.
5. Configure the OSPF area to consolidate traffic from a single network. This configures the OSPF area for IPv6 traffic.
```
SLX (conf-if-Ve-22)# ipv6 ospf area 1
SLX (conf-if-Ve-22)# 
```
  You can also configure ISIS and BGP protocols.
6. Configure the IPv4 address for the VE interface. This configuration enables the transmission of IPv4 traffic through the GRE Tunnel.
```
SLX (conf-if-Ve-22)# ip address 23.23.23.2/24
SLX (conf-if-Ve-22)# 
```
7. Configure the IPv6 address for the VE interface. This configuration enables the transmission of IPv6 traffic through the GRE Tunnel.
```
SLX (conf-if-Ve-22)# ipv6 address 2301:1::1:2/64 
SLX (conf-if-Ve-22)# 
```
8. Exit out the VE interface configuration.
```
SLX (conf-if-Ve-22)# exit
SLX (config)# 
```

The following is a consolidation of the configuration commands executed to create the VE interface on one of the tunnel end points.

interface Ve 20
 vrf forwarding vrf-red 
 ip ospf area 1
 ip address 23.23.23.1/24
 ipv6 ospf area 1 
 ipv6 address 2301:1::1:1/64

The following is a consolidation of the configuration commands executed to create the VE interface on the other tunnel end point.

interface Ve 22
 vrf forwarding vrf-red 
 ip ospf area 1
 ip address 23.23.23.2/24
 ipv6 ospf area 1 
 ipv6 address 2301:1::1:2/64