3com S7906E インストール手順

 

2-8 

 

You can apply a QoS policy globally to the inbound or outbound direction of all ports.  

Follow these steps to apply the QoS policy globally: 

Enter system view 

system-view 

— 

Apply the QoS policy globally 

qos apply policy policy-name 
global { inbound | outbound }

Required 

 

A QoS policy containing any of the nest,  remark customer-vlan-id, and remark service-vlan-id 

Actions cannot be applied globally.  

 

Packet processing units fit into the data plane and the control plane depending on their functions.  

z 

At the data plane are units responsible for receiving, transmitting, and switching (that is, forwarding) 

packets, such as various dedicated forwarding chips. They deliver super processing speeds and 

throughput.  

z 

At the control plane are processing units running most routing and switching protocols and 

responsible for protocol packet resolution and calculation, such as CPUs. Compared with data 

plane units, they allow for great packet processing flexibility but have lower throughput.  

When the data plane receives packets that it cannot recognize or process, it transmits them to the 

control plane. If the transmission rate exceeds the processing capability of the control plane, which very 

likely occurs at times of DoS attacks, the control plane will be busy handling undesired packets and fail 

to handle legitimate packets correctly or timely. As a result, protocol performance is affected.  

To address this problem, you can apply a QoS policy to the control plane to take QoS actions such as 

traffic filtering or rate limiting on inbound traffic, thus ensuring that the control plane can receive, 

transmit, and process packets normally.  

Follow these steps to apply the QoS policy to the control plane: 

Enter system view 

— 

Enter control plane view (on a 
distributed device) 

control-plane slot slot-number  

Required 

Enter control plane view (on a 
distributed IRF device) 

control-plane chassis chassis-number 
slot slot-number  

Required 

Apply the QoS policy to the 
control plane 

qos apply policy policy-name 
{ inbound | outbound } 

Required