I have installed a Draytek router into a care home environment and need it to have the LAN IP of both 192.168.1.1 and 192.168.2.1. The router hands out DHCP for all client devices on the 192.168.1.X subnet but the phone system was configured by another company with static IP's in the range 192.168.2.X and with gateway 192.168.2.1.

My first thought was to use VLAN so I configured LAN P2 to be 192.168.2.1 and turned off DHCP. I connected both P1 and P2 into the network switch and it worked as i wanted but i was seeing intermittent packet loss (between 5-10%) and this was instantly fixed if I unplugged P2.

My next thought was to configure LAN1 to be 192.168.1.1 with subnet mask 255.255.252.0 (gives me 192.168.0.1-192.168.3.255) and then added an IP alias of 192.168.2.1. This worked perfectly and no packet loss but i then discovered another issue. Some of the residents have cheap TP-Link ethernet routers in their room, they take the ethernet feed and plug into the router WAN socket and it then gives them more network ports and their own wireless. The issue is that the default LAN on these is 192.168.0.1 which clashes with the subnet mask 255.255.252.0 so they no longer get an IP address on the WAN port. If i change the TP-Link lan to 192.168.5.1 it works fine but they have loads of these devices so its not a good solution.

So does anyone have a better way to set this up?

You can not connect P1 and P2 into the same switch unless the switch has been configured with vlans and you are connecting the correct ports together

Do you know if the switch has been configured with vlans ?

saqqara wrote:
You can not connect P1 and P2 into the same switch unless the switch has been configured with vlans

Any idea of how to do this then? I cant expend the subnet mask as it clashes with 192.168.0.X.

Are the 192.168.1.0 / 24 and the phone devices connected to different switches ?

Do you know if the phones have been configured with vlan settings ?

Do you know your subnet mask ? as this can overcome no setting up vlans.