Managing Trunks

This chapter contains the following sections:

About Trunks

VLAN trunks reduce networking costs by reducing the need for expensive physical connections and conserving the number of ports used on switches. The trunk connection can be passed between two switches or between a switch and a computer. Ethernet interfaces can be configured either as access ports or a trunk port, as follows:
  • An access port can have only one VLAN configured on the interface; it can carry traffic for only one VLAN.
  • A trunk port can have two or more VLANs configured on the interface; it can carry traffic for several VLANs simultaneously.

In Cisco UCS Director, you can manage trunks on the following Cisco network devices:

  • Cisco Nexus 1000 and 1110 Series switches
  • Cisco Nexus 3000 Series switches
  • Cisco Nexus 5000, 5500, and 5672 Series switches
  • Cisco Nexus 6000 Series switches
  • Cisco Nexus 7000 Series switches
  • Cisco Nexus 9300 and 9500 Series switches
  • Cisco MDS 9100 Series switches
  • Cisco MDS 9500 Series switches
  • Cisco MDS 9700 Series switches
  • Cisco IOS Devices

Note

For more detailed information about managing trunks and configuration guidelines for managing trunks, see the Cisco NX-OS Software Configuration Guides.

Configuring a Trunk

You can configure an Ethernet port as a trunk port; a trunk port transmits untagged packets for the native VLAN plus encapsulated, tagged packets for multiple VLANs.

Procedure

Step 1

Choose Physical > Network.

Step 2

On the Network page, choose the pod.

Step 3

Select the network device to be configured.

Step 4

Click Interfaces.

Step 5

Click Configure Trunk.

Choose the interface on which the trunk needs to be configured.

Step 6

In the Configure Trunk screen, complete the required fields, including the following:

Name Description

Port Name field

The name of port on which the trunk needs to be configured.

Description field

Optionally enter a description for the trunk configuration.

Native VLAN ID drop-down list

Choose the native VLAN ID to use. The default native VLAN ID is default [1].

Allowed VLANs field

Click Select. In the Select Items dialog box, check the VLAN(s) that are allowed on this trunk port.

STP Port Type drop-down list

Choose one of the following: Edge trunk, Network, or Normal.

Note 
The STP Port Type field does not appear when you choose:

  • a Cisco Nexus 1000V device

  • a Cisco Nexus 7000 Series switch for storage virtual device context (VDC)

  • a Cisco MDS 9100, 9500, or 9700 Series switch

Port Channel

Optionally, choose the channel group to which the port has to be assigned. The default channel group mode is active.

MTU

Optionally, type the MTU range. The MTU range can be between 1500 to 9216.

Copy Running configuration to Startup configuration check box

Check the box to copy the running trunk configuration to the startup configuration.

Step 7

Click Submit.

Updating a Trunk

Procedure

Step 1

Choose Physical > Network.

Step 2

On the Network page, choose the pod.

Step 3

Select the network device to be configured.

Step 4

Click Interfaces.

Select the port on which the trunk needs to be updated.

Step 5

Click Update Trunk.

Step 6

In the Trunk Configuration screen, complete the required fields, including the following:

Name Description

Port Name button

The name of port on which the trunk needs to be updated is displayed.

Action drop-down list

Choose the relevant action (Add, or Remove).

Select VLANs field

Click Select. In the Select Items dialog box, choose the appropriate VLANs. Click Select.

Copy Running configuration to Startup configuration check box

Check the check box to copy the running trunk configuration to the startup configuration.

Step 7

Click Submit.