[原]CentOS7网卡子接口的创建
OS:CentOS 7 在linux上创建vlan需要加载802.1q模块： 1.检测OS是否已经加载802.1q模块
[root@controller ~]# modinfo 8021q filename: /lib/modules/3.10.0-229.14.1.el7.x86_64/kernel/net/8021q/8021q.ko version: 1.8 license: GPL alias: rtnl-link-vlan rhelversion: 7.1 srcversion: 2C3C3989B54002FAEC13FFD depends: mrp,garp intree: Y vermagic: 3.10.0-229.14.1.el7.x86_64 SMP mod_unload modversions signer: CentOS Linux kernel signing key sig_key: E9:9F:C4:37:BD:9C:BF:B4:F1:B1:DA:87:C1:57:FF:66:56:9B:EE:66 sig_hashalgo: sha256或者：
[root@controller ~]# modinfo -F filename 8021q
/lib/modules/3.10.0-229.14.1.el7.x86_64/kernel/net/8021q/8021q.ko
或者：
[root@controller ~]# modprobe --first-time 8021q
modprobe: ERROR: could not insert '8021q': Module already in kernel
2.如果没有加载802.1q模块怎么加载？
##加载8021q模块 [root@controller ~]# modprobe 8021q##查看是否正常加载
[root@controller ~]# lsmod |grep 8021q
8021q 28808 0
garp 14384 1 8021q
mrp 18542 1 8021q
3.在父接口创建vlan子接口
3.1在父接口/etc/sysconfig/network-scripts/ifcfg-ethX 中设置
DEVICE=ethX TYPE=Ethernet BOOTPROTO=none ONBOOT=yes
3.2复制父接口并修改接口名称
cp /etc/sysconfig/network-scripts/ifcfg-ethX /etc/sysconfig/network-scripts/ifcfg-ethX.125 ## X后面的125为vlan号
3.3配置/etc/sysconfig/network-scripts/ifcfg-ethX.125
DEVICE=ethX.192 BOOTPROTO=none ONBOOT=yes IPADDR=192.168.1.1 PREFIX=24 NETWORK=192.168.1.0 VLAN=yes ##开启vlan，表明此子接口为vlan接口
4.重启网络
systemctl restart network
================================================ CONFIGURE 802.1Q VLAN TAGGING USING THE COMMAND LINE In Red Hat Enterprise Linux 7, the 8021q module is loaded by default. If necessary, you can make sure that the module is loaded by issuing the following command as root:
~]# modprobe --first-time 8021q modprobe: ERROR: could not insert '8021q': Module already in kernel
To display information about the module, issue the following command:
~]$ modinfo 8021q
See the modprobe(8) man page for more command options. 7.4.1. Setting Up 802.1Q VLAN Tagging Using ifcfg Files Configure the parent interface in /etc/sysconfig/network-scripts/ifcfg-ethX, whereX is a unique number corresponding to a specific interface, as follows:
DEVICE=ethX TYPE=Ethernet BOOTPROTO=none ONBOOT=yes
Configure the VLAN interface configuration in the /etc/sysconfig/network-scripts/directory. The configuration file name should be the parent interface plus a . character plus the VLAN ID number. For example, if the VLAN ID is 192, and the parent interface is eth0, then the configuration file name should be ifcfg-eth0.192:
DEVICE=ethX.192 BOOTPROTO=none ONBOOT=yes IPADDR=192.168.1.1 PREFIX=24 NETWORK=192.168.1.0 VLAN=yes
If there is a need to configure a second VLAN, with for example, VLAN ID 193, on the same interface, eth0, add a new file with the name eth0.193 with the VLAN configuration details. Restart the networking service in order for the changes to take effect. As root issue the following command:
~]# systemctl restart network
7.4.2. Configure 802.1Q VLAN Tagging Using ip Commands To create an 802.1Q VLAN interface on Ethernet interface eth0, with name VLAN8 and ID 8, issue a command as root as follows:
~]# ip link add link eth0 name eth0.8 type vlan id 8
To view the VLAN, issue the following command:
~]$ ip -d link show eth0.8
4: eth0.8@eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT
link/ether 52:54:00:ce:5f:6c brd ff:ff:ff:ff:ff:ff promiscuity 0
vlan protocol 802.1Q id 8 <REORDER_HDR>
Note that the ip utility interprets the VLAN ID as a hexadecimal value if it is preceded by 0x and as an octal value if it has a leading 0. This means that in order to assign a VLAN ID with a decimal value of 22, you must not add any leading zeros. To remove the VLAN, issue a command as root as follows: ~]# ip link delete eth0.8 ================ 总结：修改父接口的BOOTPROTO=manual 复制父接口， 清空内容 注入下面的内容：
DEVICE=${SECONF_ETH}.${EXTERNAL_TENANT_NETWORK_VLAN_ID}
BOOTPROTO=none
ONBOOT=ye
IPADDR=${SECOND_SUB_INTERFACE_IP}
PREFIX=24
NETWORK=${SECOND_SUB_INTERFACE_NET}
VLAN=ye