Somehow bypassing my DHCP server

[mwarren]

I have a DHCP server on my network (Windows Server 2012).
I have an OnNetworks N300 WiFi router
I have a Dell Precision M65 running Windows XP

All these devices are sitting behind a Netgear ProSecure UTM5 firewall (Century Link ISP in front).
OnNetworks N300 gets an IP perfectly within scope from the DHCP on the network (172.*.*.*). The problem happens when I connect to the OnNetworks N300, somehow I bypass the firewall and jump straight to 192.168.*.*. DHCP on the OnNetworks N300 is disabled.
Things I have noticed (aside):
The OnNetworks N300 setup has LAN settings that have the following fields and values:
---------------------------------------------------------
Device Name: N300R
IP Address: 192.168.*.*
IP Subnet Mask: 255.255.*.*
RIP Direction: Both
RIP Version: Disabled
Use Router as DHCP Server: Disabled
----------------------------------------------------------
NOTE: I tried changing the IP Address in the LAN settings on my OnNetworks N300 above to my DNS server, but I lose connectivity to the OnNetworks N300

I don't understand how I can be getting an IP outside my network from the OnNetworks N300 when the OnNetworks N300 itself is getting an IP within the network.

Please help me.

 

[rhysiam]

You have the WiFi router's LAN ip (in your above copy-paste) in the 192.168.x.x range... not your 172. range.

Is the cable that's connecting the WiFi Router to the rest of your network plugged in to the WAN port on the router? I'm guessing so. That's NOT how you want to set it up. You actually want your router running as a simple, dumb Access Point (AP), with all routing features switched off. Some routers have that as config option, others don't. The key thing is though that you need to connect your network to a LAN port on the router/ap, not the WAN port. Plugging it into the WAN port will have the router treating the rest of your network (anything not connected directly to itself) as a "wide area network"... ie, the internet.

If you can, put your router in AP mode.
Whether you can or not, connect your network to one of the router's LAN ports.

 

[BuddhaSkoota]

IP Address: 192.168.*.*

NOTE: I tried changing the IP Address in the LAN settings on my OnNetworks N300 above to my DNS server, but I lose connectivity to the OnNetworks N300

I don't understand how I can be getting an IP outside my network from the OnNetworks N300 when the OnNetworks N300 itself is getting an IP within the network.

edit: rysiam beat me to it.

First, it appears you do not have the N300 properly connected to bypass the routing functions. The N300 should be connected to your network via one of its numbered LAN ports, not the WAN or Internet port. Otherwise, devices connected to it will not see the DHCP server. Leave the WAN port unused.

You should configure it to have a LAN IP in the 172.x.x.x range outside of the DHCP scope.

Once done, your devices should be able to see the DHCP server.

 

[rhysiam]

You should configure it to have a LAN IP in the 172.x.x.x range outside of the DHCP scope.

Thanks for adding that one though... scatter brains right now I neglected to mention it.

OP -> when you say: "NOTE: I tried changing the IP Address in the LAN settings on my OnNetworks N300 above to my DNS server, but I lose connectivity to the OnNetworks N300"...

You realise each device needs a unique IP right? So don't set your WiFi IP to your DNS server, or any other device. It needs to be a unique IP address on the 172.x.x.x network, and, as @Budda noted, outside your DHCP range (so that the DHCP server won't give out that IP address to another device at a later stage).

Standard practice is to leave a range of IP addresses (often the first 20-100 or so) free for static devices like your WiFi, routers, etc, and then have the DHCP range in the .100-.200.

 

[Tom Tancredi]

I have a DHCP server on my network (Windows Server 2012).
I have an OnNetworks N300 WiFi router
I have a Dell Precision M65 running Windows XP

All these devices are sitting behind a Netgear ProSecure UTM5 firewall (Century Link ISP in front).
OnNetworks N300 gets an IP perfectly within scope from the DHCP on the network (172.*.*.*). The problem happens when I connect to the OnNetworks N300, somehow I bypass the firewall and jump straight to 192.168.*.*. DHCP on the OnNetworks N300 is disabled.
Things I have noticed (aside):
The OnNetworks N300 setup has LAN settings that have the following fields and values:
---------------------------------------------------------
Device Name: N300R
IP Address: 192.168.*.*
IP Subnet Mask: 255.255.*.*
RIP Direction: Both
RIP Version: Disabled
Use Router as DHCP Server: Disabled
----------------------------------------------------------
NOTE: I tried changing the IP Address in the LAN settings on my OnNetworks N300 above to my DNS server, but I lose connectivity to the OnNetworks N300

I don't understand how I can be getting an IP outside my network from the OnNetworks N300 when the OnNetworks N300 itself is getting an IP within the network.

Please help me.

Your problem is you tossed in a ROUTER to a network you have setup already with other hardware to perform the same jobs. The 'simpliest' answer is to go into the OnNetworks and set it in AP MODE, disabling all the 'router' functions. It will then just be a simple Wireless BRIDGE to the wired network and rely on your Windows Server based network schema.

Second point: Your Dell has NO SUPPORT, XP was abandoned, so any solutions will not exist for that hardware till you upgrade it to a CURRENT OS. Just to let you know.

 

[mwarren]

You have the WiFi router's LAN ip (in your above copy-paste) in the 192.168.x.x range... not your 172. range.

Is the cable that's connecting the WiFi Router to the rest of your network plugged in to the WAN port on the router? I'm guessing so. That's NOT how you want to set it up. You actually want your router running as a simple, dumb Access Point (AP), with all routing features switched off. Some routers have that as config option, others don't. The key thing is though that you need to connect your network to a LAN port on the router/ap, not the WAN port. Plugging it into the WAN port will have the router treating the rest of your network (anything not connected directly to itself) as a "wide area network"... ie, the internet.

If you can, put your router in AP mode.
Whether you can or not, connect your network to one of the router's LAN ports.

Thank you so much, Rhysiam. I really appreciate your help. This worked!

 

[mwarren]

IP Address: 192.168.*.*

NOTE: I tried changing the IP Address in the LAN settings on my OnNetworks N300 above to my DNS server, but I lose connectivity to the OnNetworks N300

I don't understand how I can be getting an IP outside my network from the OnNetworks N300 when the OnNetworks N300 itself is getting an IP within the network.

edit: rysiam beat me to it.

First, it appears you do not have the N300 properly connected to bypass the routing functions. The N300 should be connected to your network via one of its numbered LAN ports, not the WAN or Internet port. Otherwise, devices connected to it will not see the DHCP server. Leave the WAN port unused.

You should configure it to have a LAN IP in the 172.x.x.x range outside of the DHCP scope.

Once done, your devices should be able to see the DHCP server.

Thank you for taking the time, BuddhaSkoota. You guys helped me out so much.

 

[mwarren]

I have a DHCP server on my network (Windows Server 2012).
I have an OnNetworks N300 WiFi router
I have a Dell Precision M65 running Windows XP

All these devices are sitting behind a Netgear ProSecure UTM5 firewall (Century Link ISP in front).
OnNetworks N300 gets an IP perfectly within scope from the DHCP on the network (172.*.*.*). The problem happens when I connect to the OnNetworks N300, somehow I bypass the firewall and jump straight to 192.168.*.*. DHCP on the OnNetworks N300 is disabled.
Things I have noticed (aside):
The OnNetworks N300 setup has LAN settings that have the following fields and values:
---------------------------------------------------------
Device Name: N300R
IP Address: 192.168.*.*
IP Subnet Mask: 255.255.*.*
RIP Direction: Both
RIP Version: Disabled
Use Router as DHCP Server: Disabled
----------------------------------------------------------
NOTE: I tried changing the IP Address in the LAN settings on my OnNetworks N300 above to my DNS server, but I lose connectivity to the OnNetworks N300

I don't understand how I can be getting an IP outside my network from the OnNetworks N300 when the OnNetworks N300 itself is getting an IP within the network.

Please help me.

Your problem is you tossed in a ROUTER to a network you have setup already with other hardware to perform the same jobs. The 'simpliest' answer is to go into the OnNetworks and set it in AP MODE, disabling all the 'router' functions. It will then just be a simple Wireless BRIDGE to the wired network and rely on your Windows Server based network schema.

Second point: Your Dell has NO SUPPORT, XP was abandoned, so any solutions will not exist for that hardware till you upgrade it to a CURRENT OS. Just to let you know.

Exactly it, Tom. Thank you for taking the time. Much appreciated!