Configuring the maximum available interface bandwidth
The maximum available interface bandwidth refers to the maximum interface bandwidth used for bandwidth check when CBQ enqueues packets, rather than the actual bandwidth of the physical interface.
Configuration guidelines
Hewlett Packard Enterprise recommends that you configure the maximum available interface bandwidth to be smaller than the actual available bandwidth of the physical interface or logical link.
On a primary channel or template interface (such as dialer, BRI, PRI, or VT) configured with the qos max-bandwidth command, AF and EF queues perform queue bandwidth check and calculation based on the bandwidth specified with the qos max-bandwidth command, so do the AF and EF queues synchronized to the sub-channel interfaces (for example, VA interfaces or B channels). Sub-channel interface bandwidth is ignored. Because the QoS configurations of the primary channel interface and the sub-channel interfaces are the same, prompts are output only for the primary channel interface. If the qos max-bandwidth command is not configured, AF and EF queues on the primary channel interface calculate queue bandwidth based on 1 Gbps of bandwidth, and AF and EF queues synchronized to the sub-channel interfaces calculate queue bandwidth based on actual sub-channel interface bandwidth. If queuing on a sub-channel interface fails due to bandwidth change, the prompt will be output for the sub-channel interface.
On an MP-group interface or MFR interface configured with the qos max-bandwidth command, AF and EF perform queue bandwidth check and calculation based on the bandwidth specified with the qos max-bandwidth command. On an MP-group interface or MFR interface without the qos max-bandwidth command configured, if the sum of sub-channel bandwidth equals to or exceeds the sum of AF bandwidth and EF bandwidth, AF and EF calculate bandwidth based on the actual interface bandwidth. Otherwise, AF and EF calculate bandwidth based on 1 Gbps of bandwidth, and the message indicating insufficient bandwidth is displayed. In the latter case, the queuing function might fail to take effect.
On tunnel interfaces, subinterfaces, HDLC link bundle interfaces, or VT/dialer interfaces using PPPoE, PPPoA, PPPoEoA, PPPoFR, or MPoFR (frame relay traffic shaping is not enabled on the frame relay interface) at the data link layer, you must configure the qos max-bandwidth command to provide base bandwidth for CBQ calculation.
Configuration procedure
To configure the maximum interface available bandwidth:
Step | Command |
|---|---|
1. Enter system view. | system-view |
2. Enter interface view. | interface interface-type interface-number |
3. Configure the maximum available bandwidth of the interface. | qos max-bandwidth bandwidth |
If no maximum available bandwidth is configured for an interface, the bandwidth used for CBQ calculation is as follows:
If the interface is a physical one, the actual baud rate or rate applies.
If the interface is a VLAN interface, 1000000 kbps applies.
If the interface is an E1, MFR or any other type of logical serial interface formed by timeslots or multiple links, the total bandwidth of all member channels/links applies.
If the interface is a template interface, a VT, BRI, PRI or dialer interface for example, 1000000 kbps applies.
If the interface is a virtual interface, a tunnel or HDLC link bundle interface for example, 0 kbps applies.