I see that we set SO_REUSEADDR to false while binding to a datagram socket whereas we set it to true for stream sockets. Is there a particular reason for this?

In my setup, I have radsecproxy listening on *:2083 for UDP requests and I have a local radius server listening on localhost:3799 (among other external servers). I was looking to set a fixed source port from which radsecproxy sends out requests to the local radius server, so I added a source block to the server config like so 

} 

but I got an error saying "address already in use". I dug around and found that its because SO_REUSEADDR is not set for datagram sockets.

Is there a reason for this and if so, is there any other way to add a fixed source port to a local radius server config block?

Thanks and regards,

Harshit