I have recently set up a bridge and was reading some old emails on the list. I found some instructions from s7r on setting up obfs4 and obfs3:
Sample torrc entry for enabling obfs4 and obfs3: ExtORPort auto ServerTransportPlugin obfs3,obfs4 exec /usr/bin/obfs4proxy ServerTransportListenAddr obfs3 [::]:port ServerTransportListenAddr obfs4 [::]:port
To make the bridge even better, you can bind obfs3 and obfs4 to lower ports (< 1024), if you have them free, such as obfs3 on 80 and obfs4 on 443 (for example).
This seemed like a good idea (I am not running a web server).
I am running tor 0.2.4.27, which does not seem to support ExtORPort. From some other recommended bridge setup I had previously set ORPort to 443. I tried changing my config to:
ORPort auto ServerTransportListenAddr obfs3 0.0.0.0:80 ServerTransportListenAddr obfs4 0.0.0.0:443
(and doing the capabilities stuff, of course).
This didn't work -- obfs4 complained that 443 was in use (is that because I had previously set it for ORPort?). So, for now, I have set obfs4 to a random high port.
I will admit to being pretty confused about the recommended bridge setting for ORPort and the obfs ports (and what ExtORPort does differently). Does anyone have a recommendation for what I should do? Do I need to upgrade to tor 0.2.5?