[Monty007]

Hi, I know that ZyWall is configured but for you not to have anti-virus is playing with danger....what if the workstaion becomes infaected it could pass through to your server.
As for you issue this will take a bit of research. Fist I would try is installing another nic. Sorry yes some liffting may be involved)
When the server looses connection can you release/renew the ip without rebooting?
Are you sure there is no hardware updates? Before starting this work create a back up!