# Configuring a User-defined VLAN (Red Hat, CentOS, Oracle Linux, and EulerOS)

This section uses CentOS 6.8 (x86_64) as an example to describe how to configure a user-defined VLAN for BMSs.

The configuration methods of Red Hat, Oracle Linux, EulerOS, and CentOS are similar.

1. Use a key or password to log in to the BMS as user root.
2. On the BMS CLI, run the following command to check the NIC information:

   ip link

   Information similar to the following is displayed.

   Among the devices, eth0 and eth1 bear the VPC, and eth3 and eth5 bear the user-defined VLAN.

3. Run the following command to check whether the /etc/udev/rules.d/ directory contains the 80-persistent-net.rules file:

   ll /etc/udev/rules.d/ | grep 80-persistent-net.rules

   - If yes, and the file contains all NICs except bond0 and lo obtained in step 2 and their MAC addresses, go to step 6.
   - If no, go to step 4.
4. Run the following command to copy the /etc/udev/rules.d/70-persistent-net.rules file and name the copy as /etc/udev/rules.d/80-persistent-net.rules.

   cp -p /etc/udev/rules.d/70-persistent-net.rules /etc/udev/rules.d/80-persistent-net.rules

5. Configure the udev rules:

   Write the MAC addresses and names of NICs except eth0 and eth1 obtained in step 2 (those not contained in the /etc/udev/rules.d/70-persistent-net.rules file) to the /etc/udev/rules.d/80-persistent-net.rules file so that the names and sequence of NICs do not change after the BMS is restarted.

   Ensure that the NIC MAC address and name are lowercase letters.

   vim /etc/udev/rules.d/80-persistent-net.rules

   The modification result is as follows:

   After the modification, press Esc, enter :wq, save the configuration, and exit.

6. Run the following commands to copy the network configuration file /etc/sysconfig/network-scripts/ifcfg-bond0 to generate the /etc/sysconfig/network-scripts/ifcfg-bond1 file, and copy the /etc/sysconfig/network-scripts/ifcfg-eth0 file to generate the /etc/sysconfig/network-scripts/ifcfg-eth3 and /etc/sysconfig/network/ ifcfg-eth5 files:

   cp -p /etc/sysconfig/network-scripts/ifcfg-bond0 /etc/sysconfig/network-scripts/ifcfg-bond1

   cp -p /etc/sysconfig/network-scripts/ifcfg-eth0 /etc/sysconfig/network-scripts/ifcfg-eth3

   cp -p /etc/sysconfig/network-scripts/ifcfg-eth0 /etc/sysconfig/network-scripts/ifcfg-eth5

7. Run the following commands to edit the /etc/sysconfig/network-scripts/ifcfg-eth3 and /etc/sysconfig/network-scripts/ifcfg-eth5 files:

   - vim /etc/sysconfig/network-scripts/ifcfg-eth3

     Edit the eth3 network configuration file as follows:

         USERCTL=no
         MTU=8888
         NM_CONTROLLED=no
         BOOTPROTO=static
         DEVICE=eth3
         TYPE=Ethernet
         ONBOOT=yes
         MASTER=bond1
         SLAVE=yes

     Change the value of BOOTPROTO to static, that of DEVICE to the network device name eth3, and that of MASTER to the port name of the user-defined VLAN (bond1). Retain values of other parameters.

   - vim /etc/sysconfig/network-scripts/ifcfg-eth5

     Edit the eth5 network configuration file as follows (similar to eth3):

         USERCTL=no
         MTU=8888
         NM_CONTROLLED=no
         BOOTPROTO=static
         DEVICE=eth5
         TYPE=Ethernet
         ONBOOT=yes
         MASTER=bond1
         SLAVE=yes

8. Run the following command to edit the /etc/sysconfig/network-scripts/ifcfg-bond1 file:

   vim /etc/sysconfig/network-scripts/ifcfg-bond1

   Edit the file as follows:

       MACADDR=f4:4c:7f:3f:da:07
       BONDING_MASTER=yes
       USERCTL=no
       ONBOOT=yes
       NM_CONTROLLED=no
       BOOTPROTO=static
       BONDING_OPTS="mode=1 miimon=100"
       DEVICE=bond1
       TYPE=Bond
       IPADDR=10.10.10.3
       NETMASK=255.255.255.0
       MTU=8888

   Where,

   - Change the value of MACADDR to the MAC address of eth3 or eth5.
   - Change the value of BOOTPROTO to static.
   - Change the value of DEVICE to bond1.
   - Change the value of IPADDR to the IP address to be allocated to bond1. If the IP address planned for the user-defined VLAN does not conflict with the VPC network segment, you can plan the IP address as needed, only to ensure that BMSs communicating through the user-defined VLAN are in the same network segment as the user-defined VLAN. An example value is 10.10.10.3.
   - Set the value of NETMASK to the subnet mask of the IP address configured for bond1.

   Retain values of other parameters.

   After the modification, press Esc, enter :wq, save the configuration, and exit.

9. Run the following command to enable port group bond1 of the user-defined VLAN:

   ifup bond1

       Determining if ip address 10.10.10.3 is already in use for device bond1...

10. Perform the preceding operations to configure other BMSs.
11. After all BMSs are configured, ping the IP addresses of other BMSs from each BMS.

Parent topic: User-defined VLAN