Configuring VLAN Trunking

 

• NETWORK | Switching > VLAN Trunking
• About Trunking
• Viewing VLANs
• Editing VLANs
• Adding a VLAN Trunk Port
• Enabling a VLAN on a Trunk Port
• Deleting VLAN Trunk Ports

NETWORK | Switching > VLAN Trunking

 

• About Trunking
• Viewing VLANs
• Editing VLANs
• Adding a VLAN Trunk Port
• Deleting VLAN Trunk Ports
• Enabling a VLAN on a Trunk Port

About Trunking

Unassigned switch ports on SonicOS can function as VLAN trunk ports. You can enable or disable VLANs on the trunk ports, allowing the existing VLANs on SonicOS to be bridged to respective VLANs on another switch connected through the trunk port. SonicOS support 802.1Q encapsulation on the trunk ports. A maximum of 32 VLANs can be enabled on each trunk port.

The VLAN trunking feature provides these functions:

• Change VLAN ID’s of existing PortShield groups
• Add/delete VLAN trunk ports
• Enable/disable customer VLAN IDs on the trunk ports

The allowed VLAN ID range is 1-4094. Some VLAN IDs are reserved for PortShield use, and the reserved range is displayed on NETWORK | Switching > VLAN Trunking.

You can mark certain PortShield groups as “Trunked.” If the PortShield group is dismantled, the associated VLAN is automatically disabled on the trunk ports.

VLANs can exist locally in the form of PortShield groups or can be totally remote VLANs. You can change the VLAN ID of PortShield groups on SonicOS. This allows easy integration with existing VLAN numbering.

SonicOS does not allow changing port VLAN membership in an ad-hoc manner. VLAN membership of a port must be configured through PortShield configuration in the SonicOS management interface.

A virtual interface (called the VLAN Trunk Interface) is automatically created for remote VLANs. When the same remote VLAN is enabled on another trunk port, no new interface is created. All packets with the same VLAN tag ingressing on different trunk ports are handled by the same virtual interface. This is a key difference between VLAN sub-interfaces and VLAN trunk interfaces.

The Name column in NETWORK | System > Interfaces displays the VLAN IDs of the VLAN Trunk Interfaces for the VLAN trunks.

You can enable any VLAN, local or remote, on a VLAN trunk to allow bridging to two respective VLANs on another switch. For example, local VLAN 345 can be enabled on the VLAN trunk for port X2, which also has two remote VLANs enabled on it. Example of VLAN table with VLAN enabled shows the VLAN Table on the NETWORK | Switching > VLAN Trunking > VLAN Table page displaying the Member Port, X9, as a member of local VLANs after the VLAN is enabled on the VLAN trunk.

VLAN trunking interoperates with the Link Aggregation and Port Mirroring features. A VLAN trunk port can be mirrored, but cannot act as a mirror port itself.

Ports configured as VLAN trunks cannot be used for any other function and are reserved for use in Layer 2 only. For example, you cannot configure an IP Address for the trunk ports.

When a Trunk VLAN interface has been configured on a particular trunk port, that trunk port cannot be deleted until the VLAN interface is removed, even though the VLAN is enabled on multiple trunk ports. This is an implementation limitation.

Viewing VLANs

• Reserved VLAN Information
• VLAN Table

Reserved VLAN Information

The Reserved VLAN Information table lists the range of reserved VLAN IDs:

• Starting VLAN ID
• Ending VLAN ID

VLAN Table

Trunk Port	Interface for the Trunk port and the number of VLAN entries associated with it
VLAN ID	ID(s) of the VLAN(s)
Configure	Contains Delete icons for the VLANs

To display the VLAN ID(s) of the Trunk Port, click the Expand icon for the Trunk port. To display the VLAN ID(s) of all the Trunk Ports, click the Expand icon in the VLAN Trunks table header. To hide the VLAN ID(s), click the appropriate Collapse icon.

Editing VLANs

To edit a VLAN

1. Navigate to Switching > VLAN Trunking.
2. Click the Configure icon in the VLAN Table row for the VLAN ID you want to edit. The Edit VLAN for PortShield Host dialog displays.

3. Do one of the following:

   • Type a different VLAN ID into the VLAN ID field. You can enter any VLAN ID except the original system-specified VLAN ID or any others in the Reserved VLAN Information table.
   • Use the VLAN ID number in the VLAN ID field, which matches the one for which you clicked the Configure icon.
4. To enable trunking for this VLAN, select the Trunked checkbox. To disable trunking for this VLAN, clear the checkbox.
5. Click OK.

Adding a VLAN Trunk Port

To add a VLAN Trunk Port

1. Navigate to Switching > VLAN Trunking.

2. Under VLAN Trunks, click +Add. The Add VLAN Trunk Port dialog displays.

   

3. Select the port to add from the Trunk Port drop-down menu.
4. Click OK.

Enabling a VLAN on a Trunk Port

To enable a custom VLAN ID on a specific trunk port

1. Navigate to NETWORK | Switching > VLAN Trunking.
2. Under the VLAN Trunks table, click Enable VLAN. The Enable VLAN dialog displays.
3. Select a trunked port from the Trunked Port drop-down menu. This is the port that you want to use to trunk the VLAN ID indicated in the VLAN ID field.
4. In the VLAN ID field, type in the VLAN ID to be trunked. This can be a VLAN ID on another switch.
5. Click OK.

Deleting VLAN Trunk Ports

You can delete one VLAN trunk port, multiple ports at a time, or all ports.

To delete a VLAN trunk port

1. Navigate to NETWORK | Switching > VLAN Trunking.
2. Expand the VLAN trunk port to be deleted.
3. Click the Delete icon in the Configure column for the VLANs to be deleted. A confirmation message displays:
4. Click OK.
5. Click the Delete icon in the Configure column for the port to be deleted. A confirmation message displays:
   
6. Click OK.

To delete multiple VLAN trunk ports

1. Navigate to NETWORK | Switching > VLAN Trunking.
2. In the VLAN Trunks table, expand the VLAN trunk ports to be deleted.
3. Click the Delete icon in the Configure column for each VLAN to be deleted. A confirmation message displays:
4. Click OK for each one.
5. Select the checkboxes for the VLAN trunk ports you want to delete. Delete becomes available.
6. Click Delete. A confirmation message displays.
7. Click OK.

To delete all VLAN trunk ports

1. Navigate to NETWORK | Switching > VLAN Trunking.
2. In the VLAN Trunks table, expand the VLAN trunk ports by clicking the Expand icon in the VLAN Trunks table heading.
3. Click the Delete icon in the Configure column for each VLAN to be deleted. A confirmation message displays:
4. Select the checkbox in the VLAN Trunks table heading. Delete becomes available.
5. Click Delete. A confirmation message displays.
6. Click OK.