The Spring Boot framework provides the default embedded server (Tomcat) to run the Spring Boot application. It runs on port 8080. It is possible to change the port in Spring Boot.
If you want to change the default port you have several options. But using
application.properties option is recommended to overwrite default values.
To override the default port, we need to specify
server.port property in application.properties file.
application.properties file, we can set a custom port number for the property server.port
server.port = 9090
In the application.yml file, you can find as follows −
server: port: 9090
application.properties file, we can set a random port number for the property
server.port = 0
application.yml file, you can find it as follows −
server: port: 0
Note − If the server.port number is 0 while starting the Spring Boot application, Tomcat uses the random port number based on the availability.
We can also set the server port using the java command line argument as follows.
java -jar spring-boot-app.jar --server.port=8009
or by using the equivalent syntax:
java -jar -Dserver.port=8009 spring-boot-app.jar