func (net UbuntuNetManager) ComputeNetworkConfig(networks boshsettings.Networks) ([]StaticInterfaceConfiguration, []DHCPInterfaceConfiguration, []string, error) {
	nonVipNetworks := boshsettings.Networks{}
	for networkName, networkSettings := range networks {
		if networkSettings.IsVIP() {
			continue
		}
		nonVipNetworks[networkName] = networkSettings
	}

	staticConfigs, dhcpConfigs, err := net.buildInterfaces(nonVipNetworks)
	if err != nil {
		return nil, nil, nil, err
	}

	dnsNetwork, _ := nonVipNetworks.DefaultNetworkFor("dns")
	dnsServers := dnsNetwork.DNS
	return staticConfigs, dhcpConfigs, dnsServers, nil
}
func (net centosNetManager) SetupNetworking(networks boshsettings.Networks, errCh chan error) error {
	nonVipNetworks := boshsettings.Networks{}
	for networkName, networkSettings := range networks {
		if networkSettings.IsVIP() {
			continue
		}
		nonVipNetworks[networkName] = networkSettings
	}

	staticInterfaceConfigurations, dhcpInterfaceConfigurations, err := net.buildInterfaces(nonVipNetworks)
	if err != nil {
		return err
	}

	dnsNetwork, _ := nonVipNetworks.DefaultNetworkFor("dns")
	dnsServers := dnsNetwork.DNS

	interfacesChanged, err := net.writeNetworkInterfaces(dhcpInterfaceConfigurations, staticInterfaceConfigurations, dnsServers)
	if err != nil {
		return bosherr.WrapError(err, "Writing network configuration")
	}

	dhcpChanged := false
	if len(dhcpInterfaceConfigurations) > 0 {
		dhcpChanged, err = net.writeDHCPConfiguration(dnsServers, dhcpInterfaceConfigurations)
		if err != nil {
			return err
		}
	}

	if interfacesChanged || dhcpChanged {
		net.restartNetworkingInterfaces()
	}

	net.broadcastIps(staticInterfaceConfigurations, dhcpInterfaceConfigurations, errCh)

	return nil
}