[FreeNX-kNX] bind failed for font TCP port 11000. Error is 112

[Alastair Johnson]

On Saturday 19 April 2008, Jack Tanner wrote:
> A year ago there was a discussion regarding the message "Error: Call to
> bind failed for font TCP port 11000. Error is 112 'Address already in
> use'." Fabian said that there was nothing he could do:
>
> http://news.gmane.org/find-root.php?message_id=%3c20070423150845.87830%40gm
>x.net%3e
>
> This issue has now shown up in the !M knowledge base:
>
> http://www.nomachine.com/tr/view.php?id=TR05E01682
>
> It seems that there's a server-side configuration aspect after all, and
> perhaps there *is* something Freenx can do.

AFAIK there is nothing in the protocol for the client to tell the server that 
it already has a session using display X, A and B so please don't use those 
displays for my session. The protocol needs extending to allow this for a 
real solution to the problem.

!M are saying that it would be possible to introduce a configuration option 
for the server that adds Y to the base display number used on that server. If 
you control several servers you could set them so that Y=0 on one, Y=10 on 
the next, 20 on the next and so on. If you select the offset carefully for 
the given number of servers and users under your control it may be possible 
to remove the chance of a collision completely _for_your_servers_. If you're 
a client who connects to servers run by different admins then you're probably 
still stuffed.

IIRC it wouldn't be too hard to implement this in nxnode, but I may have 
forgotten about something. It's a bit nasty, but it might reduce the 
probability of collisions even if it's not a complete solution.