JUNOSe 8.2.x IP Services Configuration Guide > Configuring Layer 2 Services over GRE > Configuring Frame Relay over GRE

Configuring Frame Relay over GRE

Before you configure Frame Relay over GRE, configure the CPE-facing and core-facing Frame Relay interfaces. Once Frame Relay interfaces have been created, you must connect the two Frame Relay subinterfaces by layering a CBF interface above both and establishing a CBF connection.

NOTE: To configure Frame Relay interfaces, see JUNOSe Link Layer Configuration Guide, Chapter 2, Configuring Frame Relay.

To configure Frame Relay over GRE on the CPE-facing interface:

1. Specify the physical interface on which you want to configure Frame Relay. For example:

host1(config)#interface serial 1/0

host1(config-if)#frame-relay intf-type dce

2. Enable Frame Relay encapsulation.

host1(config-if)#encapsulation frame-relay ietf

3. Create and configure a Frame Relay subinterface.

host1(config-if)#interface serial 1/0.1

4. Configure a DLCI on a Frame Relay subinterface.

host1(config-if)#frame-relay interface-dlci 100 ietf

5. Create a CBF interface.

host1(config-subif)#cbf

6. Create and configure a GRE tunnel interface.

host1(config)# interface tunnel gre:east

host1(config-if)#tunnel source 20.0.0.2

host1(config-if)#tunnel destination 20.0.0.2

host1(config-if)#tunnel mtu 10240 

host1(config-if)#tunnel sequence-datagrams

7. Enable Frame Relay encapsulation.

host1(config-if)#encapsulation frame-relay ietf

host1(config-if)#frame-relay intf-type nni

8. Create and configure a Frame Relay subinterface.

host1(config-if)#interface tunnel gre:east.1

9. Configure a DLCI on a Frame Relay subinterface.

host1(config-subif)#frame-relay interface-dlci 200 ietf

10. Create a CBF interface.

host1(config-subif)#cbf

11. Create a bidirectional CBF connection between the two CBF interfaces.

host1(config)#cbf connection serial 1/0.1 tunnel gre:east.1

cbf

• Use to create a CBF interface over the Frame Relay interface that you are configuring.
• Example

host1(config-if)#cbf

• Use the no version to remove the CBF interface.

cbf connection

• Use to create a bidirectional CBF connection between two CBF interfaces.
• Note that the bidirectional connection consists of a symmetrical pair of unidirectional connections, one from interface1 to interface2 and a second from interface2 to interface1.
• Example—Create a CBF connection between a channelized T3 module in slot 1, port 0 and the GRE tunnel east

host1(config)#cbf connection serial 1/0.1 tunnel gre:east 

• Use the no version to remove an existing connection.

interface tunnel

• Use to create a GRE IP tunnel interface.
• Specify the type of tunnel as gre, and assign a name to the tunnel.
• Example

host1(config)#interface tunnel gre:east

• Use the no version to remove the tunnel.

tunnel destination

• Use to configure the remote end of the tunnel.
• Specify either the IP address of an interface on the remote router or the hostname of the remote router.

• The IP address is the address for the destination interface.
• The hostname is the name of the destination interface.

• Example 1

host1(config)#interface tunnel gre:tunnel2

host1(config-if)#tunnel destination 192.13.7.1

• Example 2

host1(config)#interface tunnel gre:tunnel2

host1(config-if)#tunnel destination remoteHost

• Use the no version to remove the destination of a tunnel.

tunnel mtu

• Use to set the MTU for the tunnel.
• Specify a value in the range 1024-10240 bytes.
• Example

host1(config-if)#tunnel mtu 1024

• Use the no version to restore the default, 10240 bytes.

tunnel sequence-datagrams

• Use to enable GRE sequence numbers.
• Specify GRE sequence numbers at both ends of the GRE tunnel.
• Example

host1(config)#tunnel sequence-datagrams

• Use the no version to disable sequence numbers.

tunnel source

• Use to configure the source of the tunnel.
• Specify either the primary IP address or the type and number of a new interface.
• Do not specify an unnumbered interface.
• Example 1

host1(config)#interface tunnel gre:boston-tunnel-1

host1(config-if)#tunnel source 192.10.2.1

• Example 2

host1(config)#interface tunnel gre:boston-tunnel-1

host1(config-if)#tunnel source atm 5/0.12

• Use the no version to remove the source of a tunnel.