Deployment Guide
1 Globally enable auto-detection of DCBx and auto-enabling of DCB on all interfaces after switch reload.
CONFIGURATION mode
dcb enable auto-detect on-next-reload
Enabling DCB To congure the Aggregator so that all interfaces are DCB enabled and ow control disabled, use the dcb enable
command.
Disabling DCB To congure the Aggregator so that all interfaces are DCB disabled and ow control enabled, use the no dcb enable
command.
dcb enable auto-detect on-next-reload Command Example
Dell#dcb enable auto-detect on-next-reload
Conguring Priority-Based Flow Control
PFC provides a ow control mechanism based on the 802.1p priorities in converged Ethernet trac received on an interface and is enabled
by default when you enable DCB.
As an enhancement to the existing Ethernet pause mechanism, PFC stops trac transmission for specied priorities (Class of Service
(CoS) values) without impacting other priority classes. Dierent trac types are assigned to dierent priority classes.
When trac congestion occurs, PFC sends a pause frame to a peer device with the CoS priority values of the trac that is to be stopped.
Data Center Bridging Exchange protocol (DCBx) provides the link-level exchange of PFC parameters between peer devices. PFC allows
network administrators to create zero-loss links for Storage Area Network (SAN) trac that requires no-drop service, while retaining
packet-drop congestion management for Local Area Network (LAN) trac.
To ensure complete no-drop service, apply the same dcb-map on all PFC and ETS enabled interfaces.
1 Create a DCB map to apply priority based ow control or enhanced transmission selection for specied priority groups and priorities.
CONFIGURATION mode
dcb-map map-name
The maximum is 32 alphanumeric characters.
2 Congure the priority group with PGID, bandwidth percentage or strict priority for ETS and PFC mode.
DCB-MAP mode
priority-group pg_num [bandwidth percentage | strict-priority] pfc [on | off]
pg_num range is from 0 to 7.
bandwidth percentage range is from 1 to 100.
Either strict-priority or bandwidth percentage can be set for ETS on the priority group.
PFC can either be enabled or disabled for the priority group.
3 Congure the priorities to priority group.
DCB-MAP mode
priority-pgid <pgid> <pgid> <pgid> <pgid> <pgid> <pgid> <pgid> <pgid>
pgid range is from 0 to 7.
Congure priority to priority group mapping from priority 0 to priority 7 in order.
4 Exit the DCB MAP conguration mode.
Data Center Bridging (DCB)
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