VLANs
VLANs
 
 
This chapter provides information on configuring an enhanced, or extended, service. The product administration guides provide examples and procedures for configuration of basic services on the system. It is recommended that you select the configuration example that best meets your service model before using the procedures in this chapter.
Sections in this chapter include:
•
Overview
•
Creating VLAN Tags
•
Configuring Subscriber VLAN Associations
 
Overview
Virtual LANs (VLANs) provide greater flexibility in the configuration and use of contexts and services.
They are configured as “tags” on a per-port basis and allow more complex configurations to be implemented. The VLAN tag allows a single physical port to be bound to multiple logical interfaces that can be configured in different contexts. Therefore, each Ethernet port can be viewed as containing many logical ports when VLAN tags are employed.
note_smallImportant: VLANs are supported in conjunction with ports on the Ethernet 10/100, Ethernet 1000 and 10 GigE line cards. (VLAN tagging is not supported for SPIO ports.) The system supports the configuration of VLANs as follows:
•
Ethernet 1000 Line Card (GELC, GLC2): 1024 VLANs per port.
•
Ethernet 10/100 Line Card (FELC): Maximum of 256 VLANs per port and a maximum of 1017 tagged VLANs and 8 untagged VLANs per card. (VLANs including tagged and/or untagged across all the ports of a single 10/100 Line Card cannot be more than 1025.)
•
Quad Gigabit Ethernet Line Card (QGLC): 511 VLANs per port, 1024 VLANs per card
•
10 GigE Line Card (XGLC): 1024 VLANs per port.
This chapter includes the following procedures:
•
Creating VLAN Tags
•
Configuring Subscriber VLAN Associations
 
Creating VLAN Tags
Use the following example to create VLANs on a port and bind them to pre-existing interfaces. For information on creating interfaces, refer to the System Administration Guide.
config
  port ethernet <slot/port>
     no shutdown
     vlan <vlan_tag_ID>
     no shutdown
     bind interface <interface_name> <context_name>
     end
Notes:
•
A maximum of 1024 VLANs can be configured per port.
•
Configure a subscriber-vlan to associate a VLAN with specific subscribers. Refer to the Configuring Subscriber VLAN Associations section of this chapter for more information.
•
Repeat this procedure as needed to configure additional VLANs for the port.
 
Verify the port configuration
Use the following command to verify the port configuration:
show port info <slot/port>
An example of this command’s output is shown below:
Port: 17/1
Port Type : 10/100 Ethernet
Description : (None Set)
Controlled By Card : 1 (Packet Accelerator Card)
Redundancy Mode : Card Mode
Redundant With : 33/1
Physical ifIndex : 285278208
Administrative State : Enabled
Configured Duplex : Auto
Configured Speed : Auto
MAC Address : 00-05-47-01-11-00
Link State : Up
Link Duplex : Unknown
Link Speed : Unknown
Untagged:
Logical ifIndex : 285278209
Operational State : Down, Active
Tagged VLAN: VID 10
Logical ifIndex : 285278210
VLAN Type : Subscriber
Administrative State : Enabled
Operational State : Up, Active
Number of VLANs : 1
Notes:
•
Optional. Repeat this configuration as needed to configure additional ports.
•
Optional. Configure VLAN-subscriber associations if needed.
•
Save your configuration as described in Saving Your Configuration.
 
Configuring Subscriber VLAN Associations
Subscriber traffic can be routed to specific VLANs based on the configuration of their user profile. Using this functionality provides a mechanism for routing all traffic from a subscriber over the specified VLAN. All packets destined for the subscriber must also be sent using only IP addresses valid on the VLAN or they will be dropped.
 
RADIUS Attributes Used
The following RADIUS attributes can be configured within subscriber profiles on the RADIUS server to allow the association of a specific VLAN to the subscriber:
 
•
SN-Assigned-VLAN-ID : In the Starent VSA dictionary
•
SN1-Assigned-VLAN-ID : In the Starent VSA1 dictionary
note_smallImportant: Since the instructions for configuring subscriber profiles differ between RADIUS server applications, this section only provides the individual attributes that can be added to the subscriber profile. Please refer to the documentation that shipped with your RADIUS server for instructions on configuring subscribers.
 
Configuring Local Subscriber Profiles
Use the configuration example below to configure VLAN associations within local subscriber profiles on the system.
note_smallImportant: These instructions assume that you have already configured subscriber-type VLAN tags according to the instructions provided in the Creating VLAN Tags section of this chapter.
config
  context <context_name>
     subscriber name <user_name>
        ip vlan <vlan_id>
        end
 
Verify the subscriber profile configuration
Use the following command to view the configuration for a subscriber profile:
show subscriber configuration username <user_name>
Notes:
•
Repeat this command for each additional subscriber.
•
Save your configuration as described in Saving Your Configuration.
 
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