Enterasys Matrix 7G4270-09 Configuration Manual page 17

Understanding QoS Configuration on the Matrix N-Series
CoS IRL Reference Mapping Table
The CoS IRL reference table uses 32 indexes or virtual rate limiters, and maps each virtual limiter
to a physical limiter or resource. An IRL reference table exists for each port group configured, and
is indexed similarly to port‐resources, as port‐group.port‐type reference. Because it is an optional
configuration, IRL references are not populated with limiters (resources), but can be configured by
you. The IRL reference table can be displayed using the show cos reference irl command.
The following example displays default values for the show cos reference irl command output:
solutions-r1(su)->show cos reference irl
Group Index Reference Type Rate Limiter
----------- --------- ---- ------------
0.0
0.0
0.0
0.0
.
.
.
0.0
0.0
0.0
0.0
0.0
0.1
0.1
0.1
0.1
.
.
.
0.1
0.1
0.1
0.1
0.1
Physical‐Limiter to reference mapping can be configured using the set cos reference irl command.
The other references not configured are indicated by rate limiter "none". You need to:
• Identify the port group for configuration
• Identify the rate‐limit reference
Configuring the CoS Index
The CoS settings table assigns a priority, a ToS value, TxQ reference and an IRL reference to a CoS
entry as follows:
CoS Index ‐ Indexes are unique IDs for each CoS settings table entry. CoS indexes 0–7 are created
by default and mapped directly to an 802.1p priority values 0–7 for backwards compatibility.
These entries cannot be removed and the 802.1p value cannot be changed. When CoS is enabled
using the set cos state enable command, indexes are assigned. Entries 0–255 are configurable for a
total of 256 CoS entries.
February 22, 2008
0 irl none
1 irl none
2 irl none
3 irl none
27 irl none
28 irl none
29 irl none
30 irl none
31 irl none
0 irl none
1 irl none
2 irl none
3 irl none
27 irl none
28 irl none
29 irl none
30 irl none
31 irl none
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