DHCP doesn't provide correct IPs when connected to router

[hfandy]

Hi,

The setup I have is, I have a router connected to the service provider which in turn is connected to TP-Link Gargoyle firmware through a cable connection.
I set up the Tp-link gargoyle router with static IP's for all connected hosts. The gargoyle works as expected and assigns correct IPs to connected hosts as long as it is disconnected from the service provider router, once it is connected to the service provider router, the IPs assigned to the connected hosts are not related to the static IP table, and looking at the status-connected hosts, the lists show a lot of UNKNOWNs.

Apparently the connection with the service provider router creates some conflict? will the change of the subnet mask to something different from the service provider router resolve the problem? or is there is any other options?

[ispyisail]

version?

any screen shots?

[Lantis]

Yes, they must be on different subnets

[ispyisail]

Yes, they must be on different subnets

+1

[hfandy]

Thank you for your replies, can you please advise how to setup the netmask on the gargoyle router so that it is on a different network from the service provider router? I am attaching screen shots of the gargoyle configuration, also please note that the software version is 1.8.1





Thank you for your help.

[Lantis]

They already seem to be on different subnets. Have you got the cable from the service provider going to the WAN port?

[dancardwell]

Hi,

The setup I have is, I have a router connected to the service provider which in turn is connected to TP-Link Gargoyle firmware through a cable connection.
I set up the Tp-link gargoyle router with static IP's for all connected hosts. The gargoyle works as expected and assigns correct IPs to connected hosts as long as it is disconnected from the service provider router, once it is connected to the service provider router, the IPs assigned to the connected hosts are not related to the static IP table, and looking at the status-connected hosts, the lists show a lot of UNKNOWNs.

Apparently the connection with the service provider router creates some conflict? will the change of the subnet mask to something different from the service provider router resolve the problem? or is there is any other options?

It sounds to me like the DHCP server on your service provider router is assigning IPs and overruling the Gargoyle router. I'd check that the cable to your service provider router on your gargoyle router is plugged into the WAN port on the gargoyle, and not a LAN port, which might make the service provider router treat it as a switch instead of a router?

Also turning DHCP off on your service provider router might solve the problem but you will need to ensure that you are using static IPs on everything connected to it.

[hfandy]

Thank you all for your replies,

I believe dancardwell is right as the DHCP of the service provider router is overriding the gargoyle DHCP I tried to connect the cable to the WAN port of the gargoyle but internet was lost, I also tried to disable DHCP on the service provider with no success. I beleiev i am setting static IP wrong between the two routers. Can you please advice the proper way to set it up? Below are screen shots of the two routers setup screens.













Thank you for your support.

[Lantis]

Two options.


1. If your service provider router can be placed into bridge mode (usually a WAN connection setting) you should do that. Leave it on the 192.168.1.X range it currently uses. Also leave DHCP on.
Connect an Ethernet cable from the LAN port of the modem to the WAN port of Gargoyle.
Set Gargoyle connection type to PPPoE and enter your details. Set the router ip to something in the 192.168.2.X range. Notice the third octet is different to the service provider range.
That should get you going.

2. Leave the service provider settings as they are but enable DHCP again if you disabled it. Plug an Ethernet cable from LAN of modem to WAN of gargoyle. Set gargoyle connection type to DHCP wired. Set the router IP in the 192.168.2.X. Notice how the third octet is different to the service provider range.
That should get you going.


Both methods are equivalent.

[hfandy]

Thank you all for your advises. The issue is now resolved as follows:

1- On the ISP router the following was set

LAN Interface Setup:
IP Address: 192.168.1.1
Sub Net Mask: 255.255.255.0
DHCP: Server
DHCP Client Range: 192.168.1.2 : 192.168.1.50

2- TP Link Routre with gargoyle

Internet / Wan
Connect Via: DHCP Wired

Local Area Network / LAN

Router IP: 192.168.2.1
Subnet mask : 255.255.255.0
The DHCP on this router automatically set all IPs to 192.168.2.XX, the static IP table automatically updated as well. This resolved all the issues and connected computers gets the right IP address.