---
name: "ng_vlan"
section: "4"
platform: "linux"
package: "freebsd-manpages"
version: "6.0-5"
release: "Debian 4.0 (Etch)"
platforms: ["linux", "freebsd"]
url: "https://new.carta.tech/ng_vlan"
---

# ng\_vlan(4)

IEEE 802.1Q VLAN tagging netgraph node type

## NAME

**ng\_vlan** – IEEE 802.1Q VLAN tagging netgraph node type

## SYNOPSIS

**#include \<sys/types.h\>**

**#include \<netgraph.h\>**

**#include \<netgraph/ng\_vlan.h\>**

## DESCRIPTION

The **vlan** node type multiplexes frames tagged according to the IEEE 802.1Q standard between different hooks.

Each node has two special hooks, *downstream* and *nomatch*, and an arbitrary number of “vlan” hooks, each associated with a particular VLAN tag.

An ETHERTYPE\_VLAN frame received on the *downstream* hook with a tag that the node has been configured to filter is sent out the corresponding “vlan” hook. If it does not match any of the configured tags, or is not of a type ETHERTYPE\_VLAN, it is sent out the *nomatch* hook. If the *nomatch* hook is not connected, the packet is dropped.

An Ethernet frame received on the *nomatch* hook is passed unmodified to the *downstream* hook.

An Ethernet frame received on any of the “vlan” hooks is tagged accordingly and sent out the *downstream* hook.

## HOOKS

This node type supports the following hooks:

- *downstream*

  Typically this hook would be connected to a [ng\_ether(4)](/ng_ether/4.md) node, using the *lower* hook.

- *nomatch*

  Typically this hook would also be connected to an [ng\_ether(4)](/ng_ether/4.md) type node using the *upper* hook.

- ⟨*any valid name*⟩

  Any other hook name will be accepted and should later be associated with a particular tag. Typically this hook would be attached to an [ng\_eiface(4)](/ng_eiface/4.md) type node using the *ether* hook.

## CONTROL MESSAGES

This node type supports the generic control messages, plus the following:

- NGM\_VLAN\_ADD\_FILTER (addfilter)

  Associates a hook with the tag.

- NGM\_VLAN\_DEL\_FILTER (delfilter)

  Disassociates a hook from the tag.

- NGM\_VLAN\_GET\_TABLE (gettable)

  Returns a table of all hook/tag associations.

## EXAMPLES

```
#!/bin/sh
ETHER_IF=rl0
ngctl -f- <<EOF
shutdown ${ETHER_IF}:
mkpeer ${ETHER_IF}: vlan lower downstream
name ${ETHER_IF}:lower vlan
connect ${ETHER_IF}: vlan: upper nomatch
EOF
ngctl mkpeer vlan: eiface vlan123 ether
ngctl msg vlan: addfilter '{ vlan=123 hook="vlan123" }'
```

## SHUTDOWN

This node shuts down upon receipt of a NGM\_SHUTDOWN control message, or when all hooks have been disconnected.

## SEE ALSO

[netgraph(4)](/netgraph/4.md), [ng\_eiface(4)](/ng_eiface/4.md), [ng\_ether(4)](/ng_ether/4.md), [ngctl(8)](/ngctl/8.md), [nghook(8)](/nghook/8.md)

## HISTORY

The **ng\_vlan** node type appeared in FreeBSD 4.10.

## AUTHORS

Ruslan Ermilov ⟨ru@FreeBSD.org⟩