buildup of Windows time_wait talking to fbsd 4.10

[laffer1]

On Mon, 10 Jan 2005, Len Conrad wrote:

>
> We have a windows mailserver that relays its outbound to a fbsd gateway.  We 
> changed to a different fbsd gateway running 4.10. Windows then began having 
> trouble sending to 4.10.  Windows "netstat -an" shows  dozens of lines like 
> this:
>
>         source IP              desitination IP
> ======================================================================
>  TCP    10.1.16.3:1403         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1407         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1415         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1419         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1435         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1462         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1470         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1473         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1478         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1493         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1504         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1507         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1508         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1521         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1526         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1546         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1550         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1568         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1571         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1589         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1592         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1616         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1620         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1629         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1644         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1647         192.168.200.59:25      TIME_WAIT
>  TCP    10.1.16.3:1654         192.168.200.59:25      TIME_WAIT
>
> Eventually, the windows SMTP logs line like "cannot connect to remote IP" or 
> "address already in use" because no local tcp/ip sockets are available, we 
> think.
>
> The new gateway/fbsd 4.10 "sockstat -4" shows no corresponding tcp 
> connections when the Windows server is showing as above.  On the fbsd 4.10 
> machines, smtp logs, syslog, and dmesg show no errors.
>
> We switch the windows box to smtp gateway towards the old box/fbsd 4.7, all 
> is cool.
>
> Suggestions with how to proceed debugging, please.
>
> I'm trying to get the dmesg.boot for the 4.7 and 4.10 boxes now, sorry.
>
> Len

Just off the top of my head...

You mentioned the freebsd machine is the gateway.  Do you have a firewall 
on the host blocking connections from the windows machine?  Do you have a 
different kernel configuration between 4.7 and 4.10?  i.e. do you have 
something like ipdivert, etc in the kernel on one box and not the other? 
Can the windows machine ping the ip 192.168.200.59 as its a different 
class C?

Luke