Port 8080 — alternate HTTP

Port 8080 is the most common 'alternate HTTP' port — used by proxies, Tomcat, Jenkins, and apps that don't want to require sudo (port <1024 needs root on Unix).

beginner Alternate HTTP / proxies / Tomcat

Find the process + connect / kill

lsof -i :8080

# Test what's responding:
curl -I http://localhost:8080/
# Server: Apache-Coyote/1.1   → Tomcat
# X-Jenkins: 2.x             → Jenkins
# Server: Apache             → Apache HTTPD

# httpwut for full header analysis:
curl -sI http://localhost:8080/ | httpwut

Typical services on this port

Apache Tomcat (default 8080)
Jenkins (default 8080)
Spring Boot embedded server (default)
Docker registry (sometimes)
Squid / privoxy / mitmproxy (configured)

Alternatives

Adjacent: 8000 (often dev frameworks), 8081 (next-up alternate), 8443 (alternate HTTPS), 9090 (Prometheus, JMX).

Common pitfalls

Input	Result
⚠ Multiple JVMs (Tomcat, Jenkins, Spring Boot, Elasticsearch) all default to 8080 — first-started wins, others fail silently. Set explicit port in config.
⚠ 8080 is unprivileged — non-root users can bind. Useful for dev, but exposes services without sudo.
⚠ Browser default for proxy (HTTP) is 8080. If your app responds with HTML and the browser thinks it's a proxy, you get weird behavior.

Edge cases & caveats

Common use cases

Identifying which JVM service is running
Reverse proxy debugging
Tomcat / Jenkins setup
Multi-service dev environment

See what's bound to your local ports

portcheck shows pid, command, user, address — faster than netstat, simpler than ss. Linux + macOS, zero dependencies, MIT-licensed.

Open portcheck

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