# Configuring an OSPF virtual link

Use the following procedure to create an OSPF virtual link.

## Prerequisites

- Install the Advanced License.

- Enable IP routing globally on the switch.

- Assign an IP address to the VLAN that you want to enable with OSPF.

  Routing is automatically enabled on the VLAN when you assign an IP address to it.

## Procedure steps

1. From the navigation tree, double-click IP Routing.

2. In the IP Routing tree, double-click OSPF.

3. In the work area, click the Virtual If tab.

4. In the toolbar, click Insert.

5. Using the fields provided, create a new OSPF virtual link.

6. Click Insert.

## Variable definitions

The following table describes the fields of the Virtual If tab.

Field | Description
--- | ---
AreaId | Specifies the unique ID of the area that connects to the interface. An area ID of 0.0.0.0 indicates the OSPF backbone.
Neighbor | Specifies the router ID of the virtual neighbor.
TransitDelay | Specifies the estimated number of seconds required to transmit a link state update packet over the virtual interface. The transit delay is expressed as an integer between 1 and 3600. The default value is 1.
RetransInterval | Specifies the number of seconds between link state advertisement retransmissions for adjacencies that belong to the virtual interface. The retransmit interval is also used for database description and link state request packets. The retransmit interval is expressed as an integer between 1 and 3600. The default value is 5.
HelloInterval | Specifies the interval, in seconds, between the hello packets sent by the router on the virtual interface. This value must be the same for all routers that attach to a common network. The hello interval is expressed as an integer between 1 and 65535. The default value is 10.
RtrDeadInterval | Specifies the number of seconds that a neighbor router waits to receive transmitted hello packets from this interface before the neighbor declares it down. The retransmit dead interval is expressed as an integer between 1 and 2147483647. The retransmit dead interval must be a multiple of the hello interval, and must be the same for all routers that attach to a common network. The default value is 60.
AuthType | Specifies the interface authentication type. The available authentication types are: none, simplePassword, or MD5.
AuthKey | Specifies the interface authentication key used with the simplePassword authentication type.
PrimaryMd5Key | Specifies the MD5 primary key. If no MD5 primary key exists, the value in this field is 0.
State | Specifies the OSPF virtual interface state.
Events | Specifies the number of times the virtual interface has changed state or the number of times an error has occurred.
Type | Specifies whether the virtual interface is broadcast or passive.