I have a Cisco 831 router on my home network. I have a number of devices inside my network, all programmed with private, static IP addresses.
I also have a Linksys PAP2-NA v1 VOIP adapter which I am running two telephone lines with. Something very weird is going on.
I keep setting a static IP address, subnet mask, gateway, domain, and two DNS server addresses in the VOIP device. I set the DHCP option to 'No'. It also resets the password I put into the unit in the user section.
Once I've programmed the static IP address into the unit, within a few hours the DHCP option miraculously changes to 'On' again and it takes one of my dynamic IP addresses from the Cisco 831 router. I've spoken with the VOIP provider about this. According to their engineers, they send an instruction for the unit to change from static to dynamic as part of an instruction set they send the unit.
Linksys spoke of something called a 'Profile rule' that might be causing this. They suggested that I set the static IP address in the unit and turn off the DHCP again then disconnect the Ethernet cable and leave it sitting all day while I was gone. I did so and left early in the morning.
When I returned that evening, I reconnected the Ethernet cable. It was still at the static IP address I had assigned, the DHCP option was still off, and the password was still the one I had programmed.
Within ten minutes of being back on my network, it happened again. The unit got one of my dynamic IP addresses, turned the DHCP option to 'On', and reset the password I had given it to the default one my VOIP provider had put into it.
It really irritates the hell out of me that they would change my IP settings on my unit.
I am wondering if there is some way to tell my Cisco 831 that when the MAC address associated with the VOIP device requests a dynamic IP address to have the DHCP client ignore the request. Is there a way to do that? Can anyone tell me how?
I don't know that this idea will solve the problem, but I'd like to give it a try. I've sent an email of complaint to their company CEO. We'll see if it makes any difference.