SpringBoot's @MultipartConfig maxFileSize not taking effect

With Spring Boot 2.0, you should use this in your application.yml

spring:
  servlet:
    multipart:
      max-file-size: 100MB
      max-request-size: 100MB

From documentation:

Spring Boot embraces the Servlet 3 javax.servlet.http.Part API to support uploading files. By default, Spring Boot configures Spring MVC with a maximum size of 1MB per file and a maximum of 10MB of file data in a single request. You may override these values, the location to which intermediate data is stored (for example, to the /tmp directory), and the threshold past which data is flushed to disk by using the properties exposed in the MultipartProperties class. For example, if you want to specify that files be unlimited, set the spring.servlet.multipart.max-file-size property to -1.

Extracted from Appendix A of documentation

spring.servlet.multipart.max-file-size=1MB # Max file size. Values can use the suffixes "MB" or "KB" to indicate megabytes or kilobytes, respectively.

spring.servlet.multipart.max-request-size=10MB # Max request size. Values can use the suffixes "MB" or "KB" to indicate megabytes or kilobytes, respectively.

If you just want to control the multipart properties, you can use multipart.max-file-size and multipart.max-request-size properties. For example, you could raise the max size to 100Mb by adding following piece of configurations in your application.properties file:

multipart.max-file-size=100MB
multipart.max-request-size=100MB

Values can use the suffixed MB or KB to indicate a Megabyte or Kilobyte size.

Under the hood, Spring Boot will create a MultipartConfigElement based on MultipartProperties and that MultipartConfigElement will be used in Servlet registration, as stated in Spring MVC documentation. You can take a look at MultipartAutoConfiguration and DispatcherServletConfiguration and Checkout Spring Boot documentation for more information.

With spring-boot 1.5.3 you should use the following code in application.yml

spring:
 http:
  multipart:
   max-file-size: 100MB
   max-request-size: 100MB

Make sure to use spaces and not tab in your yaml file.