lldptool-pfc(8) - Linux man page

Name

PFC - Show / manipulate PFC TLV configuration

Synopsis

lldptool -t -i ethx -V PFC { willing | enabled | delay | numtcs }

lldptool -T -i ethx -V PFC <-c CONFIG_ARG ...>

CONFIG_ARG :=

enableTx = {yes|no} |

willing = {0|1} |

enabled = [0..7],[0..7],... |

delay = integer

Description

The PFC TLV is used to display and set current PFC TLV attributes.

Arguments

enableTx

Enable the PFC TLV to be transmitted in the LLDP PDU for the specified interface.
willing: Display or set willing attribute. If set and peer TLV is received the peer PFC attributes will be used. If cleared locally configured attributes are used.
enabled: Display or set priorities with PFC enabled. The set attribute takes a comma separated list of priorities to enable.
delay
Display or set delay attribute used to configure PFC thresholds in hardware buffers. If PFC is enabled and frames continue to be dropped due to full hardware buffers increasing this value may help.

Theory of Operations

The PFC TLV uses Symmetric attribute passing meaning the attributes used will depend on the willing bit. If the willing bit is enabled and a peer TLV is received the peers attributes will be used. If the willing bit is set to 0 the local attributes should be used. When both the peer and local configuration are willing a tie breaking scheme is used. For more detailed coverage see the specification.

EXAMPLE & USAGE

Enable PFC for priorities 1, 2, and 4 on eth2

lldptool -T -i eth2 -V PFC enabled=1,2,4
Display priorities enabled for PFC on eth2: lldptool -t -i eth2 -V PFC -c enabled
Display last transmitted PFC TLV on eth2: lldptool -t -i eth2 -V PFC

Source

IEEE 802.1Qaz

(http://www.ieee802.org/1/pages/dcbridges.html)

Notes

Author

John Fastabend