# `add_rtadv` Command

## Name

`add_rtadv`

## Synopsis

```
add_rtadv ${interface}
```

## Description

Adds the network defined by the specified `${interface}` to the list of
interfaces to be advertised by `rtadvd`.  

The internal implementation prevents adding duplicate interfaces to the
advertisement list, by checking for their presence before adding.
It can safely be used alongside manual changes to `rc.conf` changes to
the `rtadvd_interfaces` variable.

Additionally, the `${rc_router_dir}/rc.d/generate_rtadvd_conf` service script
will generate `${rc_router_gen_dir}/rtadvd.conf` with `${interface}:tc=settings`
lines therein which can be used by the `rtadvd` that comes with FreeBSD.
Various `rc.router` [variables](variables.md) can be used to control the global
settings for all advertised IPv6 networks.

## Examples

```
add_rtadv xy0.123 # Adds `xy0.123` to `rtadvd_interfaces`
add_rtadv abc3.765 # Adds `abc3.765` to `rtadvd_interfaces`
```

## See Also
 - [`add_net`](add_net.md)
 - [`add_vlan`](add_vlan.md)