Port not closing down upon quitting Transmission

[Lord of the Rings]

This is a problem that was not uncommon with some earlier p2p file-sharing programs.

I noticed this the other day and was suspicious all the stealth attempts in my firewall console might have been Transmission related. I use more than one file-sharing protocol.

Today might have confirmed the issue. I had not used any other file-sharing program today and my computer had been shutdown overnight for a change. Checking the firewall reports via Console on OSX 10.6.8, I noticed I was almost being DDoS'd from ip addresses from worldwide using Stealth mode. All were attempting to connect via the same port Transmission was using. This has continued for a couple of hours after Transmission was closed down. Strange thing is I only use Transmission for two private torrent sites. And I am not sure these sites even have as many members as all the addresses reported.

This does seem to be somewhat of a security issue. I would be happy if I am wrong.

I noticed when checking Transmission's preferences that the port check site was down.

Edit: I just searched which clients use port 51413 viewtopic.php?f=4&t=6951 which is not the port I use. I noticed several days ago I was being DDoS'd via that port and reported on the Gnutella Forums this port should be blocked in their firewalls. Now I know which application uses it by default, I may rescind my advice. Question is, why did I get the impression I was being DDoS'd via that port. I would consider 3-12 pings/second a DDoS attempt. I could not imagine the two private torrent sites I am a member of doing that so consistently.

Edit again: at least on this occasion, I notice all connection attempts via the port Transmission was using appear to be via UDP. Two main ports they seem to be attempting to connect through on this occasion, the one my Transmission uses and port 64358 with just a few using port 51413. When this is non-stop for so long after Transmission was quit, it is worry-some.


I opened up Vuse which I use for public torrents. No such issues.

On a side note, last update of Transmission did not result in errors from one of the private torrent sites which is highly fussy about over-connections over a period of time. I'm guessing Transmission paused the seeding files during start-up after it detected an update. Good work there!

Transmission Version: 2.73

[Lord of the Rings]

As I edited in later ... sorry you must have replied in meantime .. this is non-stop and Vuse does not do this despite it uses many public torrent sites. I tried opening Vuse, shutdown. All went quiet with its connections minutes after closing down.

If nobody from the private torrent sites has been downloading from me then I am not sure why so many would want to connect to me.

[Lord of the Rings]

I want to thank you for your response. Whilst I am still concerned the attempts through the same ports lasted for a couple of hours, whereas Vuse's public site equivalents only lasted 10-15 mins, I do understand.