Transmission port 51413 seems open but connections do not work

[urbaman]

Hi,

I’m trying to check why Transmission says port 51413 is open, I see it open from the outside, I telnet to it (getting the connection closed after a few seconds by foreign host), and I cannot connect to trackers (both http and udp). I see no traffic on 51413 on the host.

Transmission logs:

[migrations] started
[migrations] no migrations found
───────────────────────────────────────

      ██╗     ███████╗██╗ ██████╗
      ██║     ██╔════╝██║██╔═══██╗
      ██║     ███████╗██║██║   ██║
      ██║     ╚════██║██║██║   ██║
      ███████╗███████║██║╚██████╔╝
      ╚══════╝╚══════╝╚═╝ ╚═════╝

   Brought to you by linuxserver.io
───────────────────────────────────────

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───────────────────────────────────────
GID/UID
───────────────────────────────────────

User UID:    1000
User GID:    1000
───────────────────────────────────────

[custom-init] No custom files found, skipping...
Connection to localhost (127.0.0.1) 9091 port [tcp/*] succeeded!
[ls.io-init] done.

Netstat from the container:

netstat -tulpn
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0 0.0.0.0:51413           0.0.0.0:*               LISTEN      -
tcp        0      0 0.0.0.0:9091            0.0.0.0:*               LISTEN      -
tcp        0      0 :::51413                :::*                    LISTEN      -
udp        0      0 0.0.0.0:54533           0.0.0.0:*                           -
udp        0      0 0.0.0.0:6771            0.0.0.0:*                           -
udp        0      0 0.0.0.0:51413           0.0.0.0:*                           -
udp        0      0 :::51413                :::*                                -

Screenshots:

I did port forwarding both on my router and on my pfsense firewall.

Tcpdump on the host shows no traffic on the port, only on 9091.

Is there something else I’m not checking? Is there something else I can do?

I also tried out qbittorrent with same problems.

Thank you very much.

[urbaman]

Ok, turns out it was a Suricata rule on my pfSense firewall!

All working flawlessly now!