S-VLAN Oversubscription

When you configure S-VLAN subinterfaces over Ethernet interfaces to support dynamic PPPoE subinterfaces, you can take advantage of S-VLAN oversubscription.

The maximum number of S-VLANs that you can create per I/O module or IOA with PPPoE major interfaces stacked over them is greater than the maximum number of dynamic PPPoE subinterfaces. The maximum number of PPP interfaces supported per line module is directly proportional to the maximum number of PPPoE subinterfaces.

As a result, you can oversubscribe S-VLANs by configuring up to the maximum number of S-VLANs supported on the I/O module or IOA, knowing that no more than the maximum number of supported PPP sessions can be connected to the router at any one time.

For information about the module combinations that support S-VLAN oversubscription, see S-VLAN Oversubscription in Configuring VLAN and S-VLAN Subinterfaces .

For specific information about the maximum number of S-VLANs supported per I/O module or IOA and the maximum number of PPP interfaces and PPPoE subinterfaces supported per line module, see JUNOSe Release Notes, Appendix A, System Maximums.

Note: S-VLAN oversubscription is not currently supported for S-VLANs configured over bridged Ethernet interfaces. The E120 and E320 routers can support up to two IOAs per line module. This maximum number of S-VLANs per line module does not change whether one or two IOAs are installed. For more information about configuration options for the ES2-S1 GE-4 IOA, see chapter Configuring Ethernet Interfaces in JUNOSe Physical Layer Configuration Guide.

atm pvc

• Use to configure a PVC on an ATM interface. Specify one of the following encapsulation types:
  • aal5autoconfig—Enables autodetection of the 1483 encapsulation (LLC/SNAP or VC multiplexed).
  • aal5snap—Specifies a logical link control (LLC) encapsulated circuit; the LLC/Subnetwork Access Protocol (LLC/SNAP) header precedes the protocol datagram.
  • aal5mux ip—Specifies a VC multiplexed circuit. This option is used for IP only.
• Example

  host1(config-subif)#atm pvc 6 0 11 aal5autoconfig

• Use the no version to remove the specified PVC.
• See atm pvc.

encapsulation pppoe

• Use to configure PPPoE as the encapsulation method for the interface.
• Example

  host1(config-if)#encapsulation pppoe

• Use the no version to remove PPPoE encapsulation from the interface.
• See encapsulation pppoe.

encapsulation vlan

• Use to configure VLAN as the encapsulation method for the interface.
• Example

  host1(config-if)#encapsulation vlan

• Use the no version to remove VLAN encapsulation from the interface.
• See encapsulation vlan.

interface atm

• Use to select an ATM interface or ATM 1483 subinterface.
• For information about specifying the ATM interface or subinterface, see interface atm.
• Examples

  host1(config)#interface atm 5/0.1

  host1(config)#interface atm 4/0/2.1

• Use the no version to remove the interface or subinterface.
• See interface atm.

interface fastEthernet

• Use to select a Fast Ethernet interface.
• Example

  host1(config)#interface fastEthernet 4/1

• Use the no version to remove IP from an interface or a subinterface. You must issue the no version from the highest level down; you cannot remove an interface or a subinterface if the one above it still exists.
• See interface fastEthernet.

interface gigabitEthernet

interface tenGigabitEthernet

• Use to select a Gigabit Ethernet interface or a 10-Gigabit Ethernet interface.
• To specify a Gigabit Ethernet interface for ERX-7xx models, ERX-14xx models, and ERX-310 routers, use the slot/port[.subinterface ] format.
• To specify a Gigabit Ethernet interface or a 10-Gigabit Ethernet interface for E120 and E320 routers, use the slot/adapter/port[.subinterface ] format.
• For more information, see chapter Configuring Ethernet Interfaces in JUNOSe Physical Layer Configuration Guide.
• Examples

  host1(config)#interface gigabitEthernet 1/0

  host1(config)#interface gigabitEthernet 4/0/1

  host1(config)#interface tenGigabitEthernet 4/0/1

• Use the no version to remove IP from an interface. You must issue the no version from the highest level down; you cannot remove an interface or subinterface if the one above it still exists.
• See interface gigabitEthernet.
• See interface tenGigabitEthernet.

ip address

• Use to assign an IP address and subnet mask to an interface or a subinterface.
• Example

  host1(config-if)#ip address 192.1.1.1 255.255.255.0

• Use the no version to remove an IP address or disable IP processing.
• See ip address.

pppoe auto-configure

• Use to set up the router to dynamically create PPPoE subinterfaces on the PPPoE major interfaces.
• Example

  host1(config-subif)#pppoe auto-configure

• Use the no version to remove this configuration.
• See pppoe auto-configure.

pppoe profile

• Use to assign a profile to a static PPPoE major interface. The profile configuration is used to dynamically configure an upper bridged Ethernet, IP, PPP, or PPPoE interface.
• Specify a profile name with up to 80 alphanumeric characters.
• The default encapsulation type, any, applies to any autoconfigured encapsulation that does not have a specific profile assignment.
• Examples

  host1(config-subif)#pppoe profile pppoeProfile4

  host1(config-if)#pppoe profile any anyProfile

• Use the no version to remove the profile assignment from the interface.
• See pppoe profile.

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
  • 9100—Specifies Ethertype value 0x9100, which is the default
  • 9200—Specifies Ethertype value 0x9200
• 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.
• Issue the svlan id command before any upper bindings are made, such as IP or PPPoE.
• Example

  host1(config-if)#svlan id 4 255

• There is no no version.
• See svlan id.

vlan id

• Use to specify the VLAN ID.
• Use a VLAN ID that is in the range 0–4095 and is unique within the Ethernet interface.
• Issue the vlan id command before any upper bindings are made, such as IP or PPPoE.
• Use the optional keyword untagged to specify that frames be sent untagged. The keyword is valid only for VLAN ID 0, which can receive tagged frames but sends out untagged frames.
• Example

  host1(config-if)#vlan id 400

• There is no no version.
• See vlan id.

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