# Configuring an S-VLAN Subinterface

Tasks to configure a S-VLAN subinterface include:

- Configuring an S-VLAN Subinterface
- Configuring PPPoE over an S-VLAN

## Configuring an S-VLAN Subinterface

To configure an S-VLAN subinterface:

1. Specify a Fast Ethernet, Gigabit Ethernet, or 10-Gigabit Ethernet port.
   host1(config)#interface fastEthernet 4/0
2. Specify VLAN as the encapsulation method.
   host1(config-if)#encapsulation vlan

   The VLAN major interface is added.

3. Create a VLAN subinterface by adding a subinterface number to the interface identification command.
   host1(config-if)#interface fastEthernet 4/1.1
4. Assign an S-VLAN ID and a VLAN ID for the subinterface.
   host1(config-if)#svlan id 4 255
5. Assign an S-VLAN Ethertype.
   host1(config-if)#svlan ethertype 88a8

## Configuring PPPoE over an S-VLAN

To configure PPPoE over an S-VLAN over an Ethernet interface:

1. Specify a Fast Ethernet, Gigabit Ethernet, or 10-Gigabit Ethernet port.
   host1(config)#interface fastEthernet 4/0
2. Specify VLAN as the encapsulation method.
   host1(config-if)#encapsulation vlan

   The VLAN major interface is added.

3. Create a VLAN subinterface by adding a subinterface number to the interface identification command.
   host1(config-if)#interface fastEthernet 4/1.1
4. Assign an S-VLAN ID and a VLAN ID for the subinterface.
   host1(config-if)#svlan id 4 255
5. Assign an S-VLAN Ethertype.
   host1(config-if)#svlan ethertype 88a8
6. Specify PPPoE as the encapsulation method on the interface.
   host1(config-if)#pppoe
7. Create a PPPoE subinterface.
   host1(config-if)#pppoe subinterface fastEthernet 4/1.1.1
8. Specify PPP as the encapsulation method on the interface.
   host1(config-if)#encapsulation ppp
9. Assign an IP address and mask.
   host1(config-if)#ip address 164.10.6.61 255.255.255.0
10. (Optional) Configure additional PPPoE subinterfaces by completing Steps 7 through 9 using unique numbering.

Figure 18 shows one S-VLAN subinterface with multiple PPPoE subinterface stacks.

| Note: Before you can remove an S-VLAN/VLAN subinterface, you must remove the upper-layer interface stack.

Figure 18: Example of PPPoE over S-VLAN Stacking Configuration Procedure

encapsulation ppp

- Use to configure PPP as the encapsulation method for the interface.
- Use the no version to remove PPP as the encapsulation method on the interface.
- See encapsulation ppp.

encapsulation vlan

- Use to configure VLAN as the encapsulation method for the interface.
- Use the no version to remove VLAN as the encapsulation method on the interface.
- See encapsulation vlan.

ip address

- Use to set a primary or secondary IP address for an interface or subinterface.
- Specify the layer 2 encapsulation before you set the IP address.
- Use the no version to remove an IP address or disable IP processing.
- See ip address.

pppoe

- Use to configure PPPoE as the encapsulation method on the interface.
- Use the no version to disable PPPoE on the interface.
- See pppoe.

pppoe subinterface fastEthernet

- Use to create a PPPoE subinterface on a Fast Ethernet interface.
- Use the no version to remove a PPPoE subinterface on a Fast Ethernet interface.
- See pppoe subinterface.

pppoe subinterface gigabitEthernet

pppoe subinterface tenGigabitEthernet

- Use to create a PPPoE subinterface on a Gigabit Ethernet interface or on a 10-Gigabit Ethernet interface.
- Use the no version to remove a PPPoE subinterface on a Gigabit Ethernet interface or on a 10-Gigabit Ethernet interface.
- See pppoe subinterface.

svlan ethertype

- Use to assign an Ethertype value for the S-VLAN subinterface.
- Choose one of the following Ethertype values:
  - 8100—Specifies Ethertype value 0x8100, as defined in IEEE Standard 802.1q
  - 88a8—Specifies Ethertype value 0x88a8, as defined in draft IEEE Standard 802.1ad
  - 9100—Specifies Ethertype value 0x9100, which is the default
- Use an Ethertype value that matches the Ethertype value set on the customer premises equipment (CPE) to which your router connects.
- Example
  host1(config-if)#svlan ethertype 8100
- Use the no version to restore the default value, 9100.
- See svlan ethertype.

svlan id

- Use to assign S-VLAN IDs and VLAN IDs to VLAN subinterfaces.
- Use S-VLAN ID and VLAN ID numbers that are in the range 0–4095 and that are unique within the Ethernet interface.
- Use the mac-address keyword to specify a unique MAC address for the VLAN subinterface. When you do not specify a unique MAC address, the VLAN uses the MAC address of the Ethernet interface.
- Examples
  host1(config-if)#svlan id 4 255 host1(config-if)#svlan id 4 255 mac-address 0090.1a01.1234
- Issue the svlan id command before any upper bindings are made, such as IP or PPPoE.
- There is no no version.
- See svlan id.