OK. I think I found the problem... Turns out, I had a stacked switch configuration (ie: Switch 1 plugged into Switch 2, Switch 2 plugged into Router) causing collisions on the network which can eventually cause the EVL-3 card to drop off.
After investigating, I found that Switch 1 was connected to Switch 2 from "port to port" instead of "Uplink port to port". After correcting this mistake and rebooting Switch 1, the problem went away. Running without fail 2 days and counting. So far so good...
To confirm this in your situation, try removing all connections to your Switch except the EVL-3 Card and your Uplink to the Router. If the problem goes away, try plugging in each of the remaining connections, one at a time until the problem returns. The device causing the problem should then become evident and you can begin troubleshooting from there...
Network Supervision Fault/Restore
Moderators: EyezOnRich, GrandWizard
Re: Network Supervision Fault/Restore
Network supervision works very well.You need to make sure is not your ISP provider!Run a ping test(ping Google for example)signal at modem should be 0/45 sn38-40 .signal limits for modem:-8 to +8 for downstream and for upstream 34-50.sn 34 to 40. If you are not in between this signal levels its about time to call your ISP provider!!!