Deployment Guide

show interfaces Command Example: DCB disabled and Flow Control enabled
Dell#show running-config interface te 0/4
!
interface TenGigabitEthernet 0/4
mtu 12000
portmode hybrid
switchport
auto vlan
flowcontrol rx on tx off
dcb-map DCB_MAP_PFC_OFF
!
protocol lldp
advertise management-tlv management-address system-name
dcbx port-role auto-downstream
no shutdown
Dell#
When DCB is Enabled When an interface receives a DCBx protocol packet, it automatically enables DCB and disables link-level ow
control. The dcb-map and ow control congurations are removed as shown in the following example.
show interfaces Command Example: DCB enabled and Flow Control disabled
Dell#show running-config interface te 0/3
!
interface TenGigabitEthernet 0/3
mtu 12000
portmode hybrid
switchport
auto vlan
!
protocol lldp
advertise management-tlv management-address system-name
dcbx port-role auto-downstream
no shutdown
Dell#
When no DCBx TLVs are received on a DCB-enabled interface for 180 seconds, DCB is automatically disabled and ow control is re-
enabled.
Lossless Trac Handling In auto-DCB-enable mode, Aggregator ports operate with the auto-detection of DCBx trac. At any moment,
some ports may operate with link-level ow control while others operate with DCB-based PFC enabled.
As a result, lossless trac is ensured only if trac ingresses on a PFC-enabled port and egresses on another PFC-enabled port.
Lossless trac is not guaranteed when it is transmitted on a PFC-enabled port and received on a link-level ow control-enabled port, or
transmitted on a link-level ow control-enabled port and received on a PFC-enabled port.
Enabling DCB on Next Reload To congure the Aggregator so that all interfaces come up with DCB enabled and ow control disabled, use
the dcb enable on-next-reload command. Internal PFC buers are automatically congured.
1 Globally enable DCB on all interfaces after next switch reload.
CONFIGURATION mode
dcb enable on-next-reload
To recongure the Aggregator so that all interfaces come up with DCB disabled and link-level ow control enabled, use the no dcb
enable on-next-reload command. PFC buer memory is automatically freed.
Enabling Auto-DCB-Enable Mode on Next Reload To congure the Aggregator so that all interfaces come up in auto-DCB-enable mode
with DCB disabled and ow control enabled, use the dcb enable aut-detect on-next-reload command.
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Data Center Bridging (DCB)