lldptool(8)

🎀 NAME 🎀

okay so this is the lldptool(8) page from the Linux manual, and today's episode is all about vdp — show / manipulate VDP TLV configuration. periodt 💅

✨ SYNOPSIS ✨

lldptool -t -i ethx -V vdp -c enableTx

lldptool -T -i ethx -V vdp -c enableTx=[yes|no]

lldptool -t -i ethx -V vdp -c mode

lldptool -T -i ethx -V vdp -c
mode=<mode>,<mgrid>,<typeid>,<typeidversion>,<instanceid>,<mac>,<vlan>

lldptool -t -i ethx -V vdp -c role

lldptool -T -i ethx -V vdp -c role=[station|bridge]

💖 DESCRIPTION 💖

so here's the tea, bestie: the VSI discovery protocol (VDP) is NOT a TLV in the LLDP sense. like, at all. it's giving protocol, not TLV. it's a whole protocol for managing the association and deassociation of virtual station interfaces (VSIs) between the station and an adjacent switch. iconic behavior honestly 🦋

VDP uses ECP as transport for VDP TLVs, and an ECP frame may contain multiple VDP TLVs. and each VDP TLV contains a mode, typeid, version, instanceid, mac and vlan for a VSI. that's the whole vibe check 🌸

👑 ARGUMENTS 👑

• enableTx — enables or disables VDP. literally just on/off, bestie ✨
• mode — shows or sets modes for VSIs, and it comes with the following parameters:
  • <mode> — mode, and the options are: 0=preassociate, 1=preassociate with RR, 2=associate, 3=deassociate 🎀
  • <mgrid> — manager (database) id
  • <typeid> — VSI type id
  • <version> — VSI type id version
  • <instanceid> — VSI instance id
  • <format> — VDP filter info format
  • <mac> — VSI mac address
  • <vlan> — VSI vlan id
• role — shows or sets the role of the local machine, so it can act as either station (that's the default, no cap) or bridge 🫶

🧠 Theory of Operation 🧠

the VDP protocol is used to pre-associate, associate or deassociate VSIs to and adjacent switch. info about the VSIs gets formatted into VDP TLVs, which are then handed off to ECP for lower-level transport. and remember: each ECP frame may contain multiple VDP TLVs 🔥

there are two ways to receive VSI information in llpdad: via netlink or with lldptool. netlink is what libvirt uses to communicate VSIs to lldpad. and lldptool can be used to associate/deassociate VSIs straight from the command line — which is especially helpful for testing purposes, ngl 💀

🌈 EXAMPLE & USAGE 🌈

💫 Display if vdp is enabled on eth8

lldptool -t -i eth8 -V vdp -c enableTx

💫 Enable vdp on eth8

lldptool -T -i eth8 -V vdp -c enableTx=yes

💫 Display the currently configured VSIs for eth8

lldptool -t -i eth8 -V vdp -c mode

💫 Associate a VSI on eth8

lldptool -T -i eth8 -V vdp -c mode=2,12,1193046,1,fa9b7fff-b0a0-4893-8e0e-beef4ff18f8f,2,52:54:00:C7:3E:CE,3

💫 Display the locally configured role for VDP on eth8

lldptool -t -i eth8 -V vdp -c role

💫 Set the local role for VDP on eth8

lldptool -T -i eth8 -V vdp -c role=bridge

🍓 SOURCE 🍓

• IEEE 802.1Qbg (http://www.ieee802.org/1/pages/802.1bg.html)

🙈 NOTES 🙈

lowkey important: currently the code in lldpad reflects draft 0 of the upcoming standard. so like, it's draft energy, not final-final. ECP/VDP TLVs on the wire can be decoded with wireshark > v1.8. iykyk ⭐

🦋 SEE ALSO 🦋

• lldptool-evb(8)
• lldptool(8)
• lldpad(8)

💜 AUTHOR 💜

Jens Osterkamp

and that's a wrap, bestie 💖 this was lldptool(8), brought to you by open-lldp, dated February 2010 — yes, she's an elder icon and she still slays 👑🎀✨