Bittorent clients don't necessarily always use the same port, but they generally only use one port at a time. Pick a port, any port, and tell your client to use it always, and then just open that one port.
Note that not only do you need that port to be opened, you also need it to be forwarded to your computer if you're running behind a NAT router (which almost everyone is).
Is efw a stateful firewall? If it is, opening up one or two ports (one port per computer if you're behind a NAT) should be sufficient. Open up both TCP and UDP on those ports just to be safe. If it's not stateful... then... uh... this might be a bit tougher. Sorry if I can't be of any more help.
Bittorent clients don't necessarily always use the same port, but they generally only use one port at a time. Pick a port, any port, and tell your client to use it always, and then just open that one port.
Note that not only do you need that port to be opened, you also need it to be forwarded to your computer if you're running behind a NAT router (which almost everyone is).
Is efw a stateful firewall? If it is, opening up one or two ports (one port per computer if you're behind a NAT) should be sufficient. Open up both TCP and UDP on those ports just to be safe. If it's not stateful... then... uh... this might be a bit tougher. Sorry if I can't be of any more help.