Re: bind() udp behavior 2.6.8.1

[Jan Engelhardt]

>sorry "closed" was the wrong term here.  We are using a PIX Firewall
>Module and it keeps a state table of all connections (tcp and udp). 
>Thus when a new udp connection comes in with same high numbered source

UDP does not know connections. As such, _nobody_ can tell whether an UDP 
packet belongs to a logically existing "connection" or not.

>port and the firewall has not removed that connection from its state
>table, the firewall drops the packet.  The firewall needs about 60ms in
>order to clear that connection from the state table, so if a second udp
>request with the same high number port/ip comes thru before the firewall
>clears the connection from the state table, it will drop the connection
>(which is what we are seeing).
>
>FreeBSD seems to increment future udp requests which prevents this
>problem.  It just seems strange that the kernel would not randomize or
>increment these source ports for udp requests.

The kernel does not have problems with UDP, it's probably your firewall.

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