Lenovo Flex System Fabric CN4093, Инструкция по применению

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© Copyright Lenovo 2017 Chapter 17: FCoE and CEE
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Effects on 802.1p Quality of Service
While CEE is off (the default), the CN4093 allows 802.1p priority values to be used
for Quality of Service (QoS) configuration (see “Quality of Service” on page 215 ).
802.1p QoS default settings are shown in Table 27 on page 303 , but can be changed
by the administrator.
When CEE is turned on, 802.1p QoS is replaced by ETS (see “Enhanced
Transmission Selection” on page 316 ). As a result, while CEE is turned on, using
802.1p QoS configuration commands causes an error message to appear stating
that the CEE global ETS command must be used to configure 802.1p ‐ based QoS.
In addition, when CEE is turned on, prior 802.1p QoS settings are replaced with
new defaults designed for use with ETS priority groups (PGIDs) as shown in
Table 27 :
When CEE is on, the default ETS configuration also allocates a portion of link
bandwidth to each PGID as shown in Table 28 :
If the prior, non ‐ CEE configuration used 802.1p priority values for different
purposes, or does not expect bandwidth allocation as shown in Table 28 on
page 303 , when CEE is turned on, the administrator should reconfigure ETS
settings as appropriate.
Each time CEE is turned on or off, the appropriate ETS or 802.1p QoS default
settings shown in Table 27 on page 303 are restored, and any manual settings made
to prior ETS or 802.1p QoS configurations are cleared.
Table 27.
CEE Effects on 802.1p Defaults
802.1p QoS Configuration
With CEE Off (default)
ETS Configuration
With CEE On
Priority COSq Weight Priority COSq PGID
0 0 1 0 0 0
1 1 2 1 0 0
2 2 3 2 0 0
3 3 4 3 1 1
4 4 5 4 2 2
5 5 7 5 2 2
6 6 15 6 2 2
7 7 0 7 2 2
Table 28.
Default ETS Bandwidth Allocation
PGID Typical Use Bandwidth
0 LAN 10%
1 SAN 50%
2 Latency ‐ sensitive LAN 40%