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8.12. Verifying Network Configuration Teaming for Redundancy

Network redundancy is a process when devices are used for backup purposes to prevent or recover from a failure of a specific system. The following procedure describes how to verify the network configuration for teaming in redundancy:
Procedure
  1. Ping the destination IP from the team interface. For example:
    ~]# ping -I team0 DSTADDR
  2. View which interface is in active mode:
    ~]# teamdctl team0 state
    setup:
      runner: activebackup
    ports:
      enp1s0
        link watches:
          link summary: up
          instance[link_watch_0]:
            name: ethtool
            link: up
            down count: 0
      enp2s0
        link watches:
          link summary: up
          instance[link_watch_0]:
            name: ethtool
            link: up
            down count: 0
    runner:
      active port: enp1s0
    enp1s0 is the active interface.
  3. Temporarily remove the network cable from the host.

    Note

    There is no method to properly test link failure events using software utilities. Tools that deactivate connections, such as ip or nmcli, show only the driver’s ability to handle port configuration changes and not actual link failure events.
  4. Check if the backup interface is up:
    ~]# teamdctl team0 state
    setup:
     runner: activebackup
    ports:
     enp1s0
       link watches:
         link summary: down
         instance[link_watch_0]:
           name: ethtool
           link: down
           down count: 1
     enp2s0
       link watches:
         link summary: up
         instance[link_watch_0]:
           name: ethtool
           link: up
           down count: 0
    runner:
     active port: enp2s0
    enp2s0 is now the active interface.
  5. Check if you can still ping the destination IP from the team interface:
    ~]# ping -I team0 DSTADDR