VLAN
Virtual LANs give you the ability to sub-divide a LAN. Linux can accept VLAN tagged traffic and presents each VLAN ID as a different network interface (eg: eth0.100 for VLAN ID 100)
本文介绍如何通过 iproute2包 和 systemd-networkd 或 netctl 配置 VLAN 。
此前 Arch Linux 用 vconfig 命令设置 VLANs ,该命令已被 ip 命令取代。请确认 iproute2包 已安装。
下面的范例假定网口是 eth0,名字是 eth0.100 ,vlan id 是 100。
用下列命令添加 VLAN 网口:
# ip link add link eth0 name eth0.100 type vlan id 100
执行 ip link 命令确认 VLAN 已创建。
这个 VLAN 网口就像一个普通的物理网口,所有流经这个网口的数据包将被加上 VLAN tag 并流经它关联的物理网口(本例中的 eth0)。仅配置为相同 VLAN 的设备可接收这些数据包,否则将被丢弃。
Using a name like eth0.100 is just convention and not enforced; you can alternatively use eth0_100 or something descriptive like IPTV. To see the VLAN ID on an interface, in case you used an unconventional name:
# ip -d link show eth0.100
The -d flag shows full details on an interface:
# ip -d addr show
4: eno1.100@eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether 96:4a:9c:84:36:51 brd ff:ff:ff:ff:ff:ff promiscuity 0
vlan protocol 802.1Q id 100 <REORDER_HDR>
inet6 fe80::944a:9cff:fe84:3651/64 scope link
valid_lft forever preferred_lft forever
Now add an IPv4 address to the just created vlan link, and activate the link:
# ip addr add 192.168.100.1/24 brd 192.168.100.255 dev eth0.100 # ip link set dev eth0.100 up
To cleanly shutdown the setting before you remove the link, you can do:
# ip link set dev eth0.100 down
ex Removing a VLAN interface is significantly less convoluted
# ip link delete eth0.100
Use the following configuration files:
/etc/systemd/network/eno1.network
[Match] Name=eno1 [Network] DHCP=v4 VLAN=eno1.100 VLAN=eno1.200
/etc/systemd/network/'eno1.100.netdev
[Netdev] Name=eno1.100 Kind=vlan [VLAN] Id=100
/etc/systemd/network/'eno1.200.netdev
[Netdev] Name=eno1.200 Kind=vlan [VLAN] Id=200
Then enable systemd-networkd.service. See systemd-networkd for details.
You can use netctl for this purpose, see the self-explanatory example profiles in {{ic|/etc/netctl/examples/vlan-{dhcp,static} }}.
An annoyance is that udev may try to rename virtual devices as they are added, thus ignoring the name configured for them (in this case eth0.100).
For instance, if the following commands are issued:
# ip link add link eth0 name eth0.100 type vlan id 100 # ip link show
This could generate the following output:
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 1000
link/ether aa:bb:cc:dd:ee:ff brd ff:ff:ff:ff:ff:ff
3: rename1@eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state DOWN
link/ether aa:bb:cc:dd:ee:ff brd ff:ff:ff:ff:ff:ff
udev has ignored the configured virtual interface name eth0.100 and autonamed it rename1.
The solution is to edit /etc/udev/rules.d/network_persistent.rules and append DRIVERS=="?*" to the end of the physical interface's configuration line.
For example, for the interface aa:bb:cc:dd:ee:ff (eth0):
/etc/udev/rules.d/network_persistent.rules
SUBSYSTEM=="net", ATTR{address}=="aa:bb:cc:dd:ee:ff", NAME="eth0", DRIVERS=="?*"
A reboot should mean that VLANs configure correctly with the names assigned to them.