Queuing And Scheduling; Control Plane Protection - Lenovo RackSwitch G8264 Application Manual

Queuing and Scheduling

Control Plane Protection

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G8264 Application Guide for ENOS 8.4
The G8264 has 8 output Class of Service (COS) queues per port. If CEE is enabled,
this is changed to 3 queues per port and ETS is then used to configure the
scheduling in a manner different than what is described in this section. Each
packet's 802.1p priority determines its COS queue, except when an ACL action sets
the COS queue of the packet.
Notes:
 In stacking mode, because one COS queue is reserved for internal use, the
number of configurable COS queues is either 1 or 7.
 When vNIC operations are enabled, the total number of COS queues available is
4.
You can configure the following attributes for COS queues:
Map 802.1p priority value to a COS queue

 Define the scheduling weight of each COS queue
You can map 802.1p priority value to a COS queue, as follows:
RS G8264(config)# qos transmit­queue mapping <802.1p priority value (0‐7)>
<COS queue (0‐7)>
To set the COS queue scheduling weight, use the following command:
RS G8264(config)# qos transmit­queue weight­cos <COSq number>
<COSq weight (0‐15)>
Control plane receives packets that are required for the internal protocol state
machines. This type of traffic is usually received at low rate. However, in some
situations such as DOS attacks, the switch may receive this traffic at a high rate. If
the control plane protocols are unable to process the high rate of traffic, the switch
may become unstable.
The control plane receives packets that are channeled through protocol‐specific
packet queues. Multiple protocols can be channeled through a common packet
queue. However, one protocol cannot be channeled through multiple packet
queues. These packet queues are applicable only to the packets received by the
software and does not impact the regular switching or routing traffic. Packet queue
with a higher number has higher priority.
You can configure the bandwidth for each packet queue. Protocols that share a
packet queue will also share the bandwidth.