Configure Bridges

For EDGE networking mode, you must configure a Linux ethernet bridge on all NCs. This bridge connects your local ethernet adapter to the cluster network. Under normal operation, NCs will attach virtual machine instances to this bridge when the instances are booted.

To configure a bridge on CentOS 7 or RHEL 7, you need to create a file with bridge configuration (for example, ifcfg-brX) and modify the file for the physical interface (for example, ifcfg-ethX). The following steps describe how to set up a bridge on both CentOS 7 and RHEL 7. We show examples for configuring bridge devices that either obtain IP addresses using DHCP or statically.

  1. Install the bridge-utils package.
    yum install bridge-utils
  2. Go to the /etc/sysconfig/network-scripts directory:
    cd /etc/sysconfig/network-scripts
  3. Open the network script for the device you are adding to the bridge and add your bridge device to it. The edited file should look similar to the following:
    DEVICE=eth0
    # change the hardware address to match the hardware address your NIC uses
    HWADDR=00:16:76:D6:C9:45
    ONBOOT=yes
    BRIDGE=br0
    NM_CONTROLLED=no
    Note: The device name may vary. See the RedHat Networking Guide, Consistent Network Device Naming.
  4. Create a new network script in the /etc/sysconfig/network-scripts directory called ifcfg-br0 or something similar. The br0 is the name of the bridge, but this can be anything as long as the name of the file is the same as the DEVICE parameter, and the name is specified correctly in the previously created physical interface configuration (ifcfg-ethX).
    Important: Choose names and use them consistently for all NCs (both the file name ifcfg-br0 and the DEVICE=br0 in the file).
    • If you are using DHCP, the configuration will look similar to:
      DEVICE=br0
      TYPE=Bridge
      BOOTPROTO=dhcp
      ONBOOT=yes
      DELAY=0
    • If you are using a static IP address, the configuration will look similar to:
      DEVICE=br0
      TYPE=Bridge
      BOOTPROTO=static
      IPADDR=static_IP_address
      NETMASK=netmask
      GATEWAY=gateway
      ONBOOT=yes
  5. Enter the following command:
    systemctl restart network.service