Inbound Traffic Blocked, Check Firewall Settings May 2026

Temporarily disable the firewall to confirm the issue (do not do this in production).

The firewall is blocking the incoming (inbound) traffic.

sudo firewall-cmd --list-all Check the services and ports sections. If your port is missing, inbound traffic is blocked. inbound traffic blocked, check firewall settings

Issue: Users or services cannot connect to your server, application, or device from an external network (e.g., the internet or another subnet). Connection attempts time out or are actively rejected.

# Linux / macOS sudo netstat -tulpn | grep LISTEN # or ss -tuln netstat -an | findstr "LISTENING" Temporarily disable the firewall to confirm the issue

sudo ufw status verbose If inactive, enable it with sudo ufw enable . If active, check for rules like Deny from any or missing Allow rules for your port.

Get-NetFirewallRule | Where-Object $_.Direction -eq 'Inbound' -and $_.Enabled -eq 'True' | Format-Table DisplayName, Action Use with caution; only for testing. If your port is missing, inbound traffic is blocked

# Test TCP port nc -zv <target-ip> <port> telnet <target-ip> <port> Test with curl (HTTP) curl -v http://<target-ip>:<port>