public static boolean chooseBooleanChannelProperty(
            String listenAddressName, String propertySuffix, boolean defaultValue) {
        String globalPropertyName = "server." + propertySuffix;
        String listenAddressPropertyName = "server." + listenAddressName + "." + propertySuffix;

        Boolean value = new ChainedDynamicProperty.DynamicBooleanPropertyThatSupportsNull(
                        listenAddressPropertyName, null)
                .get();
        if (value == null) {
            value = new DynamicBooleanProperty(globalPropertyName, defaultValue)
                    .getDynamicProperty()
                    .getBoolean();
            if (value == null) {
                value = defaultValue;
            }
        }
        return value;
    }
First looks for a property specific to the named listen address of the form -
"server.${addrName}.${propertySuffix}". If none found, then looks for a server-wide property of the form -
"server.${propertySuffix}".  If that is also not found, then returns the specified default value.
zuul-core/src/main/java/com/netflix/zuul/netty/server/BaseServerStartup.java