Created: 2026/06/29 08:08:09 America/Chicago
By: admin

What This Tool Checks

The Active Mode Check tests the public TCP port that your DC++ client uses for incoming peer connections. Enter the hostname or public IP address that other users should reach, then enter the active-mode TCP port from your client settings.

Active Mode And Passive Mode

In passive mode, your client can connect out to hubs and to active users, but other passive users usually cannot connect back to you. Searches can return fewer results because many results travel through direct client-to-client paths. In active mode, your client accepts incoming TCP connections and receives UDP search replies on the configured port, so more peers can reach you directly.

What The Result Means

If the TCP port is open, the outside internet can reach your client address on that port from the hublist server. If it is closed or filtered, your router, local firewall, VPN, ISP, or client setting is probably blocking incoming connections. The UDP field is shown because DC++ active search also uses UDP, but this page cannot prove UDP without a real client reply.

Before You Test

  • Set your DC++ client to active mode and note the TCP and UDP ports.
  • Forward the same TCP and UDP ports in your router to the computer running the client.
  • Allow the client through Windows Firewall, macOS firewall, Linux firewall, or security software.
  • If you use a VPN, test the VPN-assigned port or turn the VPN off for comparison.

After The Test

When the TCP port opens, try a public hub search again and compare the number of results. If downloads still fail, test the hub protocol with Protocol Test, check the route with Traceroute, and read Active Mode Help for router examples.

Hub Active Mode Check

Open Help

Check whether your DC++ client listening ports appear reachable from outside your network.

Enter the public hostname or IP address that other DC++ users should reach when your client runs in active mode.
Enter the TCP port configured in your DC++ client active-mode connection settings.
Optional. Enter the UDP search port from your client settings. The page records it and explains the manual check because UDP cannot be proven without a listening client reply.
Optional. Enter the secure transfer or TLS port when your client exposes a separate encrypted-transfer port.

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