Configuring Tunnel Connections > Creating IP Tunnel Connections

Creating IP Tunnel Connections

An IP tunnel connection is a network-level object that links two mirrored IP tunnel interfaces (referred to in this chapter as endpoint A and endpoint B). (See Figure 5.)

Figure 5: Components of an IP Tunnel Connection

The two tunnel interfaces must identify a locally configured IP address as the source IP address and another IP address as the destination IP address. The source IP address of one IP tunnel interface is the destination IP address of the other IP tunnel interface, and vice versa.

To create an IP tunnel connection:

1. From the Configuration menu, select Create, and click IP Tunnel Connection.

The Create IP Tunnel Connection dialog box appears.

2. Type a logical name for the IP tunnel connection in the text box. (See Table 46.)
3. Create the tunnel endpoints in either of the following ways:

• Create a new IP tunnel interface for each endpoint by setting the parameters in each endpoint's group box. See Creating IP Tunnel Endpoints.
• Select an existing tunnel interface by clicking the Select Available Tunnel Interface button in the IP Tunnel Interface group box. See Selecting Available IP Tunnel Interfaces.

4. When you finish configuring each endpoint, click OK in the Create IP Tunnel Connection dialog box.

The NMC-RX application creates an IP tunnel connection.

NOTE: The Clear button in the IP Tunnel Interface group box allows you to reset the parameters to their default values.

Creating IP Tunnel Endpoints

This section describes creating the endpoints in an IP tunnel connection. You can also create the IP tunnel interfaces individually and then associate them as endpoints in a tunnel connection. See Chapter 9, Configuring IP Tunnel Interfaces.

To create the tunnel endpoints:

1. Set the parameters (Table 46).

 Table 46:  IP Tunnel Connection Parameters 

 Parameter
 Description

 Logical Name

 Name for the IP tunnel connection; maximum of 80 characters


 Device

 Device identifier. This field is automatically populated.


 Name

 Name for the IP tunnel interface; 1-80 characters, no spaces


 Mode

 IP tunnel mode for an IP tunnel: GRE or DVMRP. You must choose one or the other.


 MTU

 Maximum transmission unit setting for the IP tunnel interface; range 1024-10240; default 10240. To ensure effective function, the MTU value should be the same for both endpoints.


 IP Checksum

 Checking this box enables end-to-end check summing and causes the system to drop packets with bad checksums received on this interface. Range: enable/disable. Default: disable.
 This feature is disabled for DVMRP mode.


 Source: IP Address

 Source IP address for the IP tunnel interface. Enter a valid address, or click 
to search for and select an IP address (see Related Dialog Boxes).


 Source: Virtual Router

 The transport router associated with the source IP tunnel interface. You cannot edit this parameter once you create the tunnel interface. Once you choose a virtual router, you cannot change it. Enter a virtual router name, or click 
to search for and select a virtual router (see Related Dialog Boxes).


 Destination IP Address

 Destination IP address for the tunnel interface. Enter a valid address, or click 
to search for and select an IP address (see Related Dialog Boxes).



 

 NOTE: To select existing IP tunnel interfaces, click the Select Available Tunnel Interface button in the IP (or SMDS) Tunnel Interface group box.



 

2. Follow the instructions in Chapter 9, Configuring IP Tunnel Interfaces, for creating each endpoint.

Selecting Available IP Tunnel Interfaces

The Select GRE (or DVMRP) Tunnel Interface dialog box appears when you click the Select Available Tunnel Interface button in the IP (or GRE) Tunnel Interface group box.

1. In the Show Available List For group box, select an option.

The Show Available List filters help you to pare down the list of IP tunnel interfaces to those specifying a specific virtual router on a specific device. The filters provide the following options:

• All Virtual Routers on Device—If you choose this option, you need to enter the name of the device in the text box.
• All Devices with Virtual Router—If you choose this option, you need to enter the name of the virtual router in the text box.
• All Virtual Routers on all Devices—You need only to select this option.
  

  NOTE: You can use a wildcard format for the names of devices and virtual routers; for example, Lab* or *RX.

  
  

2. In the Constrain To group box, select an option:

• Open Ended—Only those tunnel interfaces that are not already part of a tunnel connection are displayed.
• Where Destination =—Only those IP tunnel interfaces whose destination address equals the IP address that you enter are displayed.

3. Click List.

The filtered list of device names and virtual routers appears.

4. Select the virtual router you want.

The list of tunnel interfaces for the virtual router you selected appears with each interface's source and destination IP address

5. Select the tunnel interface you want, and click OK.

The settings for the endpoint's tunnel interface appear in the Create IP (or SMDS) Tunnel Connection dialog box, as shown in the following example.

Related Dialog Boxes

The Select IP Address and Associate Virtual Router dialog boxes for the two IP tunnel connection endpoints are the same as those for individual IP tunnel interfaces, with one difference.

The Select IP Address dialog box for IP tunnel interfaces has only one filter option, whereas in the context of IP tunnel connections the same dialog box allows you to use three filter options. See Related Dialog Boxes.