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PFC uses DCB MIB IEEE 802.1azd2.5 and PFC MIB IEEE 802.1bb-d2.2.
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PFC uses DCB MIB IEEE 802.1azd2.5 and PFC MIB IEEE 802.1bb-d2.2.
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PFC is supported on specified 802.1p priority traffic (dot1p 0 to 7) and is configured per interface. However, only two lossless
queues are supported on an interface: one for Fibre Channel over Ethernet (FCoE) converged traffic and one for Internet Small
Computer System Interface (iSCSI) storage traffic. Configure the same lossless queues on all ports.
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A dynamic threshold handles intermittent traffic bursts and varies based on the number of PFC priorities contending for buffers,
while a static threshold places an upper limit on the transmit time of a queue after receiving a message to pause a specified
priority. PFC traffic is paused only after surpassing both static and dynamic thresholds for the priority specified for the port.
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By default, PFC is enabled when you enable DCB. If you have not loaded FCoE_DCB_Config and iSCSI_DCB_Config, DCB is
disabled. When you enable DCB globally, you cannot simultaneously enable link-level flow control.
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Buffer space is allocated and de-allocated only when you configure a PFC priority on the port.
Enhanced Transmission Selection
Enhanced transmission selection (ETS) supports optimized bandwidth allocation between traffic types in multiprotocol (Ethernet,
FCoE, SCSI) links.
ETS allows you to divide traffic according to its 802.1p priority into different priority groups (traffic classes) and configure bandwidth
allocation and queue scheduling for each group to ensure that each traffic type is correctly prioritized and receives its required
bandwidth. For example, you can prioritize low-latency storage or server cluster traffic in a traffic class to receive more bandwidth
and restrict best-effort LAN traffic assigned to a different traffic class.
The following figure shows how ETS allows you to allocate bandwidth when different traffic types are classed according to 802.1p
priority and mapped to priority groups.
Figure 33. Enhanced Transmission Selection
The following table lists the traffic groupings ETS uses to select multiprotocol traffic for transmission.
Table 16. ETS Traffic Groupings
Traffic Groupings
Description
Group ID
A 4-bit identifier assigned to each priority group. The range is
from 0 to 7 configurable; 8 - 14 reservation and 15.0 - 15.7 is
strict priority group..
Group bandwidth
Percentage of available bandwidth allocated to a priority group.
Group transmission selection algorithm (TSA)
Type of queue scheduling a priority group uses.
In Dell Networking OS, ETS is implemented as follows:
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ETS supports groups of 802.1p priorities that have:
Data Center Bridging (DCB)
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Содержание S4048-ON
Страница 1: ...Dell Configuration Guide for the S4048 ON System 9 9 0 0 ...
Страница 146: ...Figure 14 BFD Three Way Handshake State Changes 146 Bidirectional Forwarding Detection BFD ...
Страница 477: ...Figure 68 Inspecting Configuration of LAG 10 on ALPHA Link Aggregation Control Protocol LACP 477 ...
Страница 480: ...Figure 70 Inspecting a LAG Port on BRAVO Using the show interface Command 480 Link Aggregation Control Protocol LACP ...
Страница 481: ...Figure 71 Inspecting LAG 10 Using the show interfaces port channel Command Link Aggregation Control Protocol LACP 481 ...
Страница 522: ...Figure 87 Configuring Interfaces for MSDP 522 Multicast Source Discovery Protocol MSDP ...
Страница 523: ...Figure 88 Configuring OSPF and BGP for MSDP Multicast Source Discovery Protocol MSDP 523 ...
Страница 524: ...Figure 89 Configuring PIM in Multiple Routing Domains 524 Multicast Source Discovery Protocol MSDP ...
Страница 528: ...Figure 91 MSDP Default Peer Scenario 1 528 Multicast Source Discovery Protocol MSDP ...
Страница 529: ...Figure 92 MSDP Default Peer Scenario 2 Multicast Source Discovery Protocol MSDP 529 ...
Страница 530: ...Figure 93 MSDP Default Peer Scenario 3 530 Multicast Source Discovery Protocol MSDP ...
Страница 633: ...Policy based Routing PBR 633 ...
Страница 777: ...Figure 119 Single and Double Tag TPID Match Service Provider Bridging 777 ...
Страница 778: ...Figure 120 Single and Double Tag First byte TPID Match 778 Service Provider Bridging ...