VLANs are a way of virtually dividing up a network into many different subnetworks, also referred to as segmenting. Each segment will have its own broadcast domain and be isolated from other VLANs.
在 FreeBSD 上,要使用 VLANs 必須有網路卡驅動程式的支援,要查看那些驅動程式支援 vlan,請參考 vlan(4) 操作手冊。
When configuring a VLAN, a couple pieces of information must be known. First, which network interface? Second, what is the VLAN tag?
To configure VLANs at run time, with a
NIC of em0 and a
VLAN tag of 5 the
command would look like this:
# ifconfig em0.5 create vlan 5 vlandev em0 inet 192.168.20.20/24See how the interface name includes the NIC driver name and the VLAN tag, separated by a period? This is a best practice to make maintaining the VLAN configuration easy when many VLANs are present on a machine.
To configure VLANs at boot time,
/etc/rc.conf must be updated. To duplicate
the configuration above, the following will need to be
added:
vlans_em0="5"
ifconfig_em0_5="inet 192.168.20.20/24"Additional VLANs may be added, by simply
adding the tag to the
vlans_
field and adding an additional line configuring the network on
that VLAN tag's interface.em0
It is useful to assign a symbolic name to an interface so
that when the associated hardware is changed, only a few
configuration variables need to be updated. For example,
security cameras need to be run over VLAN 1 on
em0. Later, if the em0
card is replaced with a card that uses the ixgb(4) driver,
all references to em0.1 will not have to
change to ixgb0.1.
To configure VLAN
5, on the
NIC em0, assign the
interface name cameras, and assign the
interface an IP address of
with a 192.168.20.2024-bit prefix,
use this command:
# ifconfig em0.5 create vlan 5 vlandev em0 name cameras inet 192.168.20.20/24For an interface named video, use the
following:
# ifconfig video.5 create vlan 5 vlandev video name cameras inet 192.168.20.20/24To apply the changes at boot time, add the following lines to
/etc/rc.conf:
vlans_video="camera"
create_args_camera="vlan 5"
ifconfig_camera="inet 192.168.20.20/24"本文及其他文件,可由此下載: ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/。
若有 FreeBSD 方面疑問,請先閱讀
FreeBSD 相關文件,如不能解決的話,再洽詢
<questions@FreeBSD.org>。
關於本文件的問題,請洽詢
<doc@FreeBSD.org>。