Alternative HTTP
What is Port 8081?
Port 8081 is a common alternative HTTP port used when 8080 is occupied or for running secondary web services. It's used by various application servers, development tools, and management interfaces. Nexus Repository Manager uses port 8081 by default. React Native's Metro bundler uses port 8081 for its development server. McAfee ePolicy Orchestrator and other enterprise management tools use this port. In microservice architectures, port 8081 often serves admin or management endpoints alongside the main service on 8080. HAProxy and other load balancers may use 8081 for their stats interface.
Common Uses
- Nexus Repository Manager
- React Native Metro bundler
- Secondary web service endpoints
- Admin and management interfaces
Technical Details
Copy-paste commands to check port 8081 (Alternative HTTP) from your terminal
Test connectivity
nc -zv example.com 8081
curl -v --max-time 5 http://example.com:8081/
telnet example.com 8081
nmap -p 8081 -sV example.com
(echo > /dev/tcp/example.com/8081) 2>/dev/null && echo "open" || echo "closed"
Open port in firewall
sudo ufw allow 8081/tcp
sudo iptables -A INPUT -p tcp --dport 8081 -j ACCEPT
sudo firewall-cmd --permanent --add-port=8081/tcp && sudo firewall-cmd --reload
Security Considerations
Same considerations as port 8080. Ensure management interfaces require authentication. Don't expose development servers to external networks. Use TLS for sensitive traffic.
Popular Ports Reference
The most commonly used and referenced network ports