lldptool-dcbx(8)

👑 lldptool-dcbx — the DCBX glow-up guide 💅

okay so welcome to the lldptool-dcbx(8) page bestie, this is the one about DCBX and how to look at it, poke it, and reset it. it's giving "network admin but make it cute". let's get into it 🦋

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✨ NAME ✨

DCBX — Show / manipulate DCBX configuration

like, that's the whole job. showing it and manipulating it. main character energy fr.

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🌸 SYNOPSIS 🌸

lldptool -t -i ethx -V IEEE-DCBX -c [mode]

lldptool -T -i ethx -V IEEE-DCBX mode=reset

lldptool -t -i ethx -V <CIN-DCBX|CEE-DCBX> -c [enableTx]

lldptool -T -i ethx -V <CIN-DCBX|CEE-DCBX> enableTx=<yes|no>

look at those four little lines. iconic. that's the whole vibe of this page, everything else is lore 💖

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🧚 DESCRIPTION — DCBX MODE 🧚

so lldpad supports these versions of the DCB capabilities exchange (DCBX) protocol:

• CIN DCBX — <http://download.intel.com/technology/eedc/dcb_cep_spec.pdf>
• CEE DCBX — <http://www.ieee802.org/1/files/public/docs2008/az-wadekar-dcbx-capability-exchange-discovery-protocol-1108-v1.01.pdf>
• IEEE DCBX — See the IEEE 802.1Qaz-2011 specification for details.

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IEEE DCBX is the default DCBX mode for a DCB capable interface. so bestie, that means the default and configured IEEE DCBX TLVs get transmitted when the interface comes up. no cap. ✨

lldpad can be globally configured to support one of the legacy DCBX versions (CIN or CEE). and here's the tea 🍵: if the remote LLDP agent does not transmit any IEEE DCBX TLVs and does transmit a legacy DCBX TLV which matches the configured legacy DCBX version, then the DCBX mode will drop back to legacy DCBX mode. it will not transition back to IEEE DCBX mode until the next link reset. 😭

and if lldpad has dropped back to legacy DCBX mode for a given interface and the daemon is stopped and restarted, the legacy DCBX mode for that interface will be used instead of starting out in IEEE DCBX mode. > this behavior only applies to the case where lldpad is restarted and is not persistent across a system reboot. so don't come for me after a reboot, it resets.

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the DCBX mode can be queried and configured by using the special tlvid IEEE-DCBX. there is not an actual TLV which corresponds to this tlvid — its whole use is to query and reset the IEEE DCBX mode. when queried, IEEE DCBX mode can take the following values:

• auto — IEEE DCBX will be used (initially) if lldpad is restarted. An exception is if the DCBX mode has been forced to a legacy DCBX mode, then the specified legacy mode will be used. See information about the 'dcbx' parameter in dcbtool(8) for more information about this exception.
• CEE — CEE DCBX will be used if lldpad is restarted
• CIN — CIN DCBX will be used if lldpad is restarted

the IEEE DCBX mode can be reset to auto by setting the mode argument to the value reset 💫

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🌈 DESCRIPTION — DCBX CONFIGURATION 🌈

the detailed configuration of the IEEE DCBX TLVs lives in the related lldptool man pages for each IEEE DCBX TLV — go read lldptool-pfc(8), lldptool-ets(8) and lldptool-app(8). iykyk 🫶

the detailed configuration of the CIN and CEE DCBX TLVs is performed using dcbtool (see dcbtool(8)). however, lldptool can configure the enableTx parameter of the CIN and CEE DCBX TLVs (as it can with most other TLVs). and since lldpad only transmits TLVs for one version of DCBX on any given interface, the enableTx parameter for the CIN and CEE DCBX TLVs (and for the IEEE DCBX feature TLVs) takes effect only when the corresponding DCBX version is active. that's the catch, bestie 🙈

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🎀 ARGUMENTS 🎀

• mode=reset — Reset the DCBX mode that will be used if lldpad is restarted, by setting the mode argument to reset using the special tlvid IEEE-DCBX. like a little factory reset for your mode, but only for restart time 💅
• enableTx — Enable the specified DCBX TLV (CIN-DCBX or CEE-DCBX) to be transmitted in the LLDPDU if that DCBX mode for the specified interface has been selected. so it only actually does anything when the right mode is on, periodt.

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🔥 EXAMPLE & USAGE 🔥

Query the current DCBX mode that will be used if lldpad is restarted. (this is not a persistent setting 👀)

lldptool -t -i eth3 -V IEEE-DCBX -c mode

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Reset the DCBX mode to be 'auto' (start in IEEE DCBX mode) after the next lldpad restart

lldptool -T -i eth3 -V IEEE-DCBX mode=reset

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Enable transmission of the CEE DCBX TLV

lldptool -T -i eth3 -V CEE-DCBX enableTx=yes

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Disable transmission of the CIN DCBX TLV

lldptool -T -i eth3 -V CIN-DCBX enableTx=no

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Query the configuration of enableTx for the CEE DCBX TLV

lldptool -t -i eth3 -V CEE-DCBX -c enableTx

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💀 NOTES 💀

literally nothing here bestie. the section is empty. it's giving minimalism. we respect it. 🙈

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👑 SEE ALSO 👑

dcbtool(8), lldptool(8), lldptool-ets(8), lldptool-pfc(8), lldptool-app(8), lldpad(8)

go read them, they're all part of the same friend group 🌸

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🦋 AUTHOR 🦋

Eric Multanen

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and that's the whole page, bestie!! you slayed it 💖 this was brought to you by open-lldp, dated August 2012 — yes it's been iconic since 2012, we love a timeless queen. mwah 💅✨