[mythtv-users] Strange networking issue with Acer Revo AR1600 on GBit lan

[Daniel Born]

Hi all,

Just wondering if anyone has experienced similar strangeness with their AR1600s on Gigabit lans.

Here is a "short-as-possible" rundown of the situation:

64bit Mythbuntu 9.10 up-to-date FE/BE in basement. Full tower, Intel Core2 Duo 3GHz, 4GB RAM, 250GB system, 2x1TB data, nVidia GT-220 connected via HDMI to Sony 1080p TV (using STB to HD-PVR for data aquisition). Connected onboard GBit nic to Linksys 5-port GBit switch.

32bit Mythbuntu 9.10 up-to-date FE on AR1600 in 2nd floor bedroom. RAM upgraded to 3GB. Connected onboard NIC via wallplate to Linksys 8-port GBit switch (also in basement). In-wall ethernet cable is CAT-5e about 16 meters long.

Both switches are located within inches of each other and are connected together with straight-through cable (not crossover, yet).

All network cabling verified with borrowed-from-work Fluke network analyzer and everything passes at 1GB speed.

Problem:
It all works normally for long periods of time (30-45 minutes are typical) and suddenly, connection stalls and everything stops working until restarted and then works normally again.

I have ruled out Myth as it will do it with any networking activity such as rcp-ing files between AR1600 and other computers on network. Just an opened ssh session running 'top' (so it is busy doing something and refreshing the window) will eventually fail and close the connection. Connection cannot be re-established for several minutes (Connection refused). Meanwhile, pings work normally and ssh-ing from another machine works until it fails too.

After several debugging and analysis sessions, I narrowed it down to some sort of incompatibility between the AR1600 and the 8-port GBit switch!
If I remove _either_ one of these two pieces of equipment, the entire network is happy. Right now, I have taken out the 8-port GBit Linksys switch and I have all servers and Myth FE connected to the 5-port GBit switch and the rest (including connection to 100Mbit Linksys router) on an old 8-port 100MBit Linksys switch and it all seems to work fine.

At one point, I had the AR1600 connected to the 8-port 100mbit switch and the rest on the 8-port GBit switch and connections still failed if going through the GBit switch to the AR1600 (itself at 100mbit!)

Defective AR1600? GBit Linksys switch? other?

Any insight on what may possibly be the problem? I'm stumped.

Thanks,
Daniel