VDETAPLIB(1)

💖 VDETAPLIB(1) — vdetaplib, the tap-emulation bestie 💖

okay so bestie, this is the General Commands Manual page for vdetaplib, and it’s giving tap-emulation library main character energy. We’re going in. 💅

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✨ NAME ✨

vdetaplib - Virtual Distributed Ethernet tap emulation library. Periodt. 👑

🦋 SYNOPSIS 🦋

No synopsis.

Like, literally no synopsis. That’s the vibe. 💀

🌸 DESCRIPTION 🌸

okay so vdetaplib is a library that emulates tap — a tuntap level2 interface, see in kernel sources Documentation/networking/tun.c — and connects tap virtual interfaces to vde networks. It’s iconic, it’s niche, iykyk. 🦋

To use it, the libvdetab.so library must be preloaded. Here’s the syntax for sh, ksh or bash:

export LD_PRELOAD=/usr/lib/vde2/libvdetap.so

And for csh, tcsh syntax:

setenv LD_PRELOAD /usr/lib/vde2/libvdetap.so

bestie, yes: the library line says libvdetab.so, and the preload example says libvdetap.so. Keep the strings exactly as written. 💅

🎀 one vde_switch to rule all the taps

If you want to divert all tap requests to a single vde_switch, set the variable VDEALLTAP to the vde socket. Here’s the sh, ksh or bash syntax:

export VDEALLTAP=/tmp/vde.ctl

And the csh, tcsh syntax:

setenv VDEALLTAP /tmp/vde.ctl

🦋 per-interface switch glow-up

It is possible to set each single interface to different vde_switches by setting the environment variable with the same name of the interface. sh, ksh or bash syntax:

export tap0=/tmp/vde.ctl
export tap1=/tmp/myvde.ctl
export ppc=/tmp/ppc.ctl

csh, tcsh syntax:

setenv tap0 /tmp/vde.ctl
setenv tap1 /tmp/myvde.ctl
setenv ppc /tmp/ppc.ctl

🔥 port, group, mode

It is also possible to specify port, group or mode for a given interface by setting environment variables as in the following example. sh, ksh or bash syntax:

export tap0_port=5
export tap0_group=vde-net
export tap0_mode=0660

csh, tcsh syntax:

setenv tap0_port 5
setenv tap0_group vde-net
setenv tap0_mode 0660

🌈 fallback vibe check

The variable to set the specific interface is checked first, then VDEALLTAP. VDEALLTAP thus works as a default choice for the vde switch to be used. If VDEALLTAP is not set and there is no specific environment variable (and for tun -- IFF_TUN interfaces) the kernel provided interface is used. In this latter case access to /dev/net/tun is required, generally root access.

heads up, bestie: that /dev/net/tun access is the whole plot twist — generally root access, no cap. 👑

🚨 NOTICE 🚨

Virtual Distributed Ethernet is not related in any way with www.vde.com ("Verband der Elektrotechnik, Elektronik und Informationstechnik" i.e. the German "Association for Electrical, Electronic & Information Technologies"). Not the vibe, not the same thing, periodt. 💀

👀 SEE ALSO 👀

• vde_switch(1)
• vdeq(1)

Go peek at those, bestie. They’re in the group chat too. 🫶

💜 AUTHOR 💜

VDE is a project by Renzo Davoli <renzo@cs.unibo.it>. Slay, Renzo. 🫶

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xoxo, Virtual Distributed Ethernet 💖 December 6, 2006 💖 — that’s the source/version and date sign-off, bestie. 🎀