DCB-PFC(8)

okay bestie, this is the dcb-pfc man page (section 8) 🎀

💖 NAME 💖

dcb-pfc — show / manipulate PFC (Priority-based Flow Control) settings of the DCB (Data Center Bridging) subsystem ✨

🧚 SYNOPSIS 🧚

dcb [ OPTIONS ] pfc { COMMAND | help }

dcb pfc show dev DEV [ pfc-cap ] [ prio-pfc ] [ macsec-bypass ] [ delay
        ] [ requests ] [ indications ]

dcb pfc set dev DEV [ prio-pfc PFC-MAP ] [ macsec-bypass { on | off } ]
        [ delay INTEGER ]

PFC-MAP := [ PFC-MAP ] PFC-MAPPING

PFC-MAPPING := { PRIO | all }:{ on | off }

PRIO := { 0 .. 7 }

🦋 DESCRIPTION 🦋

okay so dcb pfc is the tool you use to configure Priority-based Flow Control attributes through the Linux DCB (Data Center Bridging) interface 💅 PFC lets you mark flows with a certain priority as lossless, and it also holds the related configuration and the PFC counters. literally the whole vibe 🌸

🌈 PARAMETERS 🌈

ngl this part is a little detailed, but it's important! For read-write parameters, we only describe the write direction, which means how it works with the set command. For the show command, you just use the parameter name as a simple keyword with no extra arguments. That tells the tool to show you the value of that parameter. If you don't give any parameters at all, the tool shows the complete PFC configuration 👑

• pfc-cap — a read-only property that shows the number of traffic classes that may simultaneously support PFC 🎀
• requests — a read-only count of the sent PFC frames per traffic class. It only shows up when -s is given, or when you ask for it explicitly 📤
• indications — a read-only count of the received PFC frames per traffic class. Same deal: it only shows up when -s is given, or when you request it explicitly 📥
• macsec-bypass { on | off } — whether the sending station is capable of bypassing MACsec processing when MACsec is disabled 🔐
• prio-pfc PFC-MAP — PFC-MAP uses the array parameter syntax, so check out dcb(8) for the full details 🧁 The keys are priorities, and the values are on / off indicators of whether PFC is enabled for that priority 💜
• delay INTEGER — the allowance made for round-trip propagation delay of the link, measured in bits. The value shall be 0..65535 ⏱️

💅 EXAMPLE & USAGE 💅

ok this is the fun part, let's see it in action ✨

Enable PFC on priorities 6 and 7, leaving the rest intact:

# dcb pfc set dev eth0 prio-pfc 6:on 7:on

Disable PFC of all priorities except 6 and 7, and configure delay to 4096 bits:

# dcb pfc set dev eth0 prio-pfc all:off 6:on 7:on delay 0x1000

Show what was set:

# dcb pfc show dev eth0
pfc-cap 8 macsec-bypass off delay 4096
prio-pfc 0:off 1:off 2:off 3:off 4:off 5:off 6:on 7:on

🙈 EXIT STATUS 🙈

Exit status is 0 if the command was successful, or a positive integer upon failure. so if you get anything other than 0, something didn't slay 💀

🔗 SEE ALSO 🔗

dcb(8) 🫶

🐛 REPORTING BUGS 🐛

found a bug? bestie, report it! Send it to the Network Developers mailing list <netdev@vger.kernel.org>, which is where the development and maintenance is primarily done. You do not have to be subscribed to the list to send a message there 📬

👑 AUTHOR 👑

Petr Machata <me@pmachata.org> 💖

that's the tea, bestie! ☕ This page is from iproute2, last updated 31 October 2020, and it's all about DCB-PFC(8) 🌈💜🦋