Inbound connections dropped

[realalehunter]

Hi. We have an Ubuntu machine that we use as a file/local web server in the office. Over the past few weeks we have been experiencing problems with connections to it inbound dropping off. We connect to it through ssh and HTTP. When it happens it affeects everyone that is already connected to it and you cannot reconnect to if for a few minutes afterwards by either SSH of HTTP.

When it happens, if you try to connect to it from a machine that hasn't been connected to it for a while it will connect fine. Also while it is down the connection FROM the server seems fine (I can browse the web from it and connect to my computer via ssh even though I cannot connect TO it from my machine).

We have tried upgrading the network card drivers, changing the network card, changing the network cable and sockets.

Nothing unusual shows in any of the log files

Output from ifconfig is
ath0 Link encap:Ethernet HWaddr 00:1B:11:00:7F:28
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)

eth0 Link encap:Ethernet HWaddr 00:01:6C:11:DC:9F
inet addr:192.168.100.124 Bcast:192.168.103.255 Mask:255.255.248.0
inet6 addr: fe80::201:6cff:fe11:dc9f/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:3396065 errors:0 dropped:0 overruns:0 frame:0
TX packets:5030105 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:733529131 (699.5 MB) TX bytes:6011348110 (5.5 GB)
Interrupt:17 Base address:0xe000

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:16333 errors:0 dropped:0 overruns:0 frame:0
TX packets:16333 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:2029143 (1.9 MB) TX bytes:2029143 (1.9 MB)

wifi0 Link encap:UNSPEC HWaddr 00-1B-11-00-7F-28-00-00-00-00-00-00-00-00-00-00
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:150500 errors:0 dropped:0 overruns:0 frame:34867
TX packets:3673 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:199
RX bytes:10904359 (10.3 MB) TX bytes:168958 (164.9 KB)
Interrupt:16


Thanks
Matt