Blade ICE G8124-E Manuale Utente

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  Chapter 14: FCoE and CEE

BMD00220, October 2010

For ETS use, each 801.2p priority value is assigned to a priority group which can then be allocated 
a specific portion of available link bandwidth. To configure a priority group, the following is 
required:

CEE must be turned on (

) for the ETS feature to 

function.

A priority group must be assigned a priority group ID (PGID), one or more 802.1p priority 
values, and allocated link bandwidth greater than 0%.

PGID

Each priority group is identified with number (0 through 7, and 15) known as the PGID.

PGID 0 through 7 may each be assigned a portion of the switch’s available bandwidth.

PGID 8 through 14 are reserved as per the 802.1Qaz ETS standard.

PGID 15 is a strict priority group. It is generally used for critical traffic, such as network 
management. Any traffic with priority values assigned to PGID 15 is permitted as much bandwidth 
as required, up to the maximum available on the switch. After serving PGID 15, any remaining link 
bandwidth is shared among the other groups, divided according to the configured bandwidth 
allocation settings.

All 802.1p priority values assigned to a particular PGID should have similar traffic handling 
requirements. For example, PFC-enabled traffic should not be grouped with non-PFC traffic. Also, 
traffic of the same general type should be assigned to the same PGID. Splitting one type of traffic 
into multiple 802.1p priorities, and then assigning those priorities to different PGIDs may result in 
unexpected network behavior.

Each 802.1p priority value may be assigned to only one PGID. However, each PGID may include 
multiple priority values. Up to eight PGIDs may be configured at any given time. However, no more 
than three ETS Priority Groups may include priority values for which PFC is disabled.