Enabling DiffServ for a port

Enable DiffServ so that the switch provides DiffServ-based Quality of Service (QoS) on the port.

About this task

Procedure

  1. In the navigation tree, expand the following folders: Configuration > QOS.
  2. Click Port QoS Config.
  3. In the row for the port, double-click the cell in the DiffServ column.
  4. Select true.
  5. Click Apply.

QoS Port Config field descriptions

Use the data in the following table to use the Port QoS Config tab.

Name

Description

Index

Specifies an index value that uniquely identifies a port.

DiffServ

Specifies whether DiffServ is enabled (true) or disabled (false) on the port. The default is true. This variable works in conjunction with Layer3Trust. The DiffServ variable is a global parameter that affects QoS DSCP operations. If the DiffServ parameter is false (DiffServ disabled), the system does not use the DSCP parameter for classification or modify it. If this variable is true, it activates the Layer3Trust parameter.

Layer3Trust

Configures the Layer 3 trusted port as an access or core port. The default is core. Core configures the port to a trusted state and access configures the port to an untrusted state. The DiffServ parameter determines the operation of this variable. If DiffServ is false, Layer3Trust has no effect; no modification of the DSCP or TOS bits occurs. If DiffServ is true, the core and access configuration take effect.

Layer2Override8021p

Specifies whether Layer 2 802.1p override is enabled (true) or disabled (false) on the port. The default is false. This variable primarily affects tagged packet treatment. If Layer2Override8021p is false, the port trusts the 802.1p-bits portion of a Q-tagged packet. The port trusts the 802.1p-bits marking regardless of the port setting (tagged or untagged); however, if the discard tagged packets parameter (DiscardTaggedFrames) on an untagged port is true, the system discards the packet. If Layer2Override8021p is true, the port does not trust the 802.1p bit marking. In this case, the QoS operation depends on other parameters, such as the port QoS level.

QosLevel

Specifies the QoS level to use when the system processes packets carried on this port. Values range from level 0–6 (the system reserves 7 for network control traffic). The default is 1.