— interface netgraph node
node is both a netgraph node and a system networking
interface. When an iface
node is created, a new interface
appears which is accessible via ifconfig(8)
node interfaces are named
, etc. When a node is shutdown, the corresponding
interface is removed and the interface name becomes available for reuse by
nodes; new nodes always take the first unused
interface. The node itself is assigned the same name as its interface, unless
the name already exists, in which case the node remains unnamed.
node has a single hook corresponding to each
supported protocol. Packets transmitted via the interface flow out the
corresponding protocol-specific hook. Similarly, packets received on a hook
appear on the interface as packets received into the corresponding protocol
stack. The currently supported protocols are IP, IPv6, AppleTalk, IPX, ATM,
NATM, and NS.
node can be configured as a point-to-point interface
or a broadcast interface. The configuration can only be changed when the
interface is down. The default mode is point-to-point.
nodes support the Berkeley Packet Filter (BPF).
This node type supports the following hooks:
- Transmission and reception of IP packets.
- Transmission and reception of IPv6 packets.
- Transmission and reception of AppleTalk packets.
- Transmission and reception of IPX packets.
- Transmission and reception of ATM packets.
- Transmission and reception of NATM packets.
- Transmission and reception of NS packets.
This node type supports the generic control messages, plus the following:
- Returns the name of the associated interface as a
NUL-terminated ASCII string. Normally this is the
same as the name of the node.
- Returns the global index of the associated interface as a
32 bit integer.
- Set the interface to point-to-point mode. The interface
must not currently be up.
- Set the interface to broadcast mode. The interface must not
currently be up.
- This message is defined by the
ng_cisco(4) node type; see ng_cisco(4)
for a description.
This node shuts down upon receipt of a
control message. The associated interface is removed and becomes available for
use by future iface
Unlike most other node types, an iface
go away when all hooks have been disconnected; rather,
control message is required.
interface supports ALTQ bandwidth management
feature. However, ng_iface
is a special case, since it is
not a physical interface with limited bandwidth. One should not turn ALTQ on
if the latter corresponds to some tunneled
connection, e.g. PPPoE or PPTP. In this case, ALTQ should be configured on the
interface that is used to transmit the encapsulated packets. In case when your
graph ends up with some kind of serial line, either synchronous or modem, the
is the right place to turn ALTQ on.
node type was implemented in