QoS mapping configuration

You can optionally change the following QoS mappings:

The mappings are globally configurable and apply to all interfaces.

Default DSCP to internal forwarding priority mappings

The DSCP values are described in RFCs 2474 and 2475. The following table lists the default mappings of DSCP values to internal forwarding priority values.

Table 1. Default DSCP to internal forwarding priority mappings

Internal forwarding priority

DSCP value

0 (lowest priority queue)

0–7

1

8–15

2

16–23

3

24–31

4

32–39

5

40–47

6

48–55

7 (highest priority queue)

56–63

Notice that DSCP values range from 0 through 63, whereas the internal forwarding priority values range from 0 through 7. Any DSCP value within a given range is mapped to the same internal forwarding priority value. For example, any DSCP value from 8 through 15 maps to priority 1.

After performing this mapping, the device maps the internal forwarding priority value to one of the hardware forwarding queues.

On ICX devices, you can use QoS queue 1 for priority traffic, even when sFlow is enabled on the port.

You can change the DSCP to internal forwarding mappings. You also can change the internal forwarding priority to hardware forwarding queue mappings.