What is running on localhost 8080?

Port 8080 is the default port for Apache Tomcat, Spring Boot applications, Jenkins CI/CD, and often Vue.js development servers.

How to fix 8080 port already in use?

You need to identify the PID occupying port 8080 using 'lsof -i :8080' (Mac/Linux) or 'netstat -ano | findstr :8080' (Windows) and kill it.

Localhost 8080 Not Working? Fix Tomcat, Vue & Spring Boot Errors

Fixing "Localhost 8080" Connection Errors

Port 8080 is the alternative HTTP standard and is widely used by Java ecosystems (Tomcat, Spring Boot), Jenkins, and Vue.js. If it's not loading, follow these steps.

Server Status

1. Is Your Backend Running?

Unlike frontend frameworks, 8080 usually hosts backend services. Ensure your JAR file or container is active.

# For Spring Boot / Java
mvn spring-boot:run

# For Vue.js (If configured to 8080)
npm run serve

Port Conflict

2. Address Already in Use (JVM_BIND)

This is a classic Java error. It means another instance of Tomcat or Jenkins is already hogging port 8080.

MacOS / Linux:

lsof -i :8080
kill -9 [PID]

Windows:

netstat -ano | findstr :8080
taskkill /PID [PID] /F

3. Firewall & Antivirus

Sometimes Windows Firewall blocks port 8080 because it looks like a public web server. Try temporarily disabling your firewall or adding an exception for java.exe.

What Uses Port 8080?

While port 80 is the standard web port, Port 8080 is the most common alternative for web servers running without root privileges.

Common Services on 8080:

Apache Tomcat: The default port for Tomcat web server.
Spring Boot: The default embedded server port.
Jenkins: The leading open-source automation server.
Vue.js: Older versions of Vue CLI default to 8080.

Changing the Port

If 8080 is crowded, you can easily switch. For Spring Boot, edit application.properties:

server.port=9090

Accessing Localhost 8080?