// more than one IP for the proxy.
		if features.EnableDualStack && len(cb.passThroughBindIPs) > 1 {
			// add extra source addresses to cluster builder
			var extraSrcAddrs []*core.ExtraSourceAddress
			for _, extraBdIP := range cb.passThroughBindIPs[1:] {
				extraSrcAddr := &core.ExtraSourceAddress{
					Address: &core.SocketAddress{
						Address: extraBdIP,