Configuration Guide User guide

FastIron Configuration Guide 1973

53-1002494-02

QoS queues

Queues for the SX-FI-8XG interface module

The SX-FI-8XG interface module consists of two separate hardware Network Processors (NP). The

front-end NP supports 8 hardware queues, and the back-end NP supports eight hardware queues.

In the egress, traffic is destined to four adjacent ports (for example, ports 1/1 to 1/4), and

aggregated into one 10GbE port in the back-end NP. The four network ports share the same

hardware queues; therefore, they have the same buffer and descriptor limits and scheduling

algorithm for transmission.

QoS classification occurs in two iterations; initially in the front-end NP, followed by the back-end NP.

The back-end NP has the same classification and marking capabilities of existing FastIron SX

interface modules, however, the front -end NP does not support ACL and static MAC priority. The

front-end NP supports basic QoS features, such as port priority, qos-tos mapping, 802.1p to priority

mapping, 802.1p override, and trust-dscp mode.

Queues for the ICX 6430 switch

For the ICX 6430 switch, ingress packets are classified into eight QoS priority levels. These are

mapped internally to four hardware forwarding queues or traffic classes as shown in Table 335.

QoS priority 7 is the highest priority, and QoS 0 is the lowest QoS priority (qosp) level.

TABLE 335 Priority queues for the ICX 6430

For the ICX 6430 switch, internal forwarding priority maps to hardware forwarding queues 0

through 3. The mapping between the internal priority and hardware forwarding queue cannot be

changed. Table 336 through Table 339 shows the default QoS mappings that are used if the trust

level for CoS or DSCP is enabled. Mappings are the same for stand-alone and stacking systems.

QoS priority level Hardware queues

(Traffic classes)

TABLE 336 Default QoS mappings for ICX 6430, columns 0 to 15

DSCP value 0123456789101112121415

802.1p (CoS)

value

0000000011111111

DSCP value0123456789101112121415