10-21-2009, 12:25 AM
space-time wrote:
for example, my Cable modem (motorola surfboard something) does not give an IP address sometimes unless you power it down and power it up again. To make that clear, if my router is plugged into the modem it works just fine, if I unplug the router and plug the PowerBook into the modem, I guess the modem is still trying to talk to the router and it will refuse to see the PowerBook unless I cycle the power OFF and back ON to the modem.
Usually that's because the modem has activated the router's MAC address, and thus your ISP only wants to see that MAC address. You have to power cycle the modem to get it to work with the new MAC address.
Similar thing happened to the link between VOIP and Router. sometimes I have to power one down and reboot it to make it talk to the other device.
It should be router first, then VOIP. The gizmo needs to get an IP from the router. If you turn it on before the router, it can't get an IP and is thus not connected to the network.
This is very inconvenient if I want to shut down everything (*) and restore power.
(*) I just replaced a switch and disconnected power from the circuit breaker. When I restored the power, the Router and one VOIP box would not work, the other VOIP and cable modem worked just fine. I had to do the unplug/plug-in dance to restore service to the Router and second VOIP box.
Overall it depends on the specific hardware you have. I'm sure if I plugged another device into my modem without power cycling it I'd have the same issue. Other than that, I don't really have those problems. That said, I'd always just do it in order of what requires what. Start with the modem, then work your way down the chain.