def ipv4_interval=(arr)
      interval, min_rx, multiplier = arr
      set_args_keys(interval: interval, min_rx: min_rx, multiplier: multiplier,
                    state: arr == default_ipv4_interval ? 'no' : '')
      config_set('bfd_global', 'ipv4_interval', @set_args)
    end
def ipv4_interval=(arr)
      interval, min_rx, multiplier = arr
      set_args_keys(interval: interval, min_rx: min_rx, multiplier: multiplier,
                    state: arr == default_ipv4_interval ? 'no' : '')
      config_set('bfd_global', 'ipv4_interval', @set_args)
    end
ipv4_interval is an array of ipv4_interval, ipv4_min_rx and
 ipv4_multiplier
 ex: ['100', '100', '25']
 CLI: bfd ipv4 interval 100 min_rx 100 multiplier 25