@gjunk 

Did you get a static IP address from Centurylink?

  @gjunk 

Hello and welcome.

First, let's say that your modem is a modem router. From your IP, that's a modem router for sure. About the VLAN that you configured on ER6120, that does not seem to be right because you are connected to a LAN(from your modem).

So, the correct settings should be:

WAN settings on ER6120, if you choose Static IP as the connection,
IP is your Static IP which y our prefer. This should be an IP from the subnet 192.168.0.1. I assume you have 192.168.0.2 to 192.168.0.254 available.

Subnet: 255.255.255.0 which corresponding with the 254 IPs avail.

Gateway IP: 192.168.0.1 which is your modem router's LAN IP.

For the DNS, you can choose whatever suitable for you. Your ISP may get their own DNS server or you choose public one like 8.8.8.8 or 1.1.1.1

VLAN, I don't think that you need a VLAN when you use a LAN connection like this. Just don't check it and put numbers there. Leave it alone.

For the LAN settings on ER6120, you choose 192.168.1.1, that's right.

When you connect a router behind a router, their LANs cannot be the same. If they both use the same subnet like 192.168.0.1, this will cause a conflict and lead to a disaster in your network.

DHCP, it's up to you.

So, that's it. Think this can help you out.

  @gjunk 

If you put the ER6120 WAN on the Centuarylink LAN subnet (192.168.0.x) with the Centuarylink LAN (192.168.0.1) as the default gateway, you should be able to access Internet. Use an IP address, not a DNS name, to test it. And, do not reuse subnets. It’s messy and you can easily get confused.

Why do you put a router behind a router? Somebody needs to have a really good reason to do that and, in a home network, there is usually none. Well, you can still use the same devices, but just eliminate one routing interface. Probably the easiest way to do that in you situation is to connect a Centuarylink LAN port to a ER6120 LAN port. Than your ER6120 LAN should be also on the Centuarylink LAN subnet. It would be also a good idea to disable the DHCP server on the ER6120.   

gjunk wrote

 

There is no vlan set up.

 

The ER6120 is set with the lan at 192.169.1.1 and dns at  8.8.8.8 and 9.9.9.9

I can reach it and login at 192.168.1.1 with my laptop set to pick up an automatic ip.

 

My modem/router is a Centurylink router with a static ip from Centurylink.

 

The internal lan on the centurylink router is on 192.168.0.1.

When I connect the century link router directly to my laptop it grabs an ip in the 192.168.0 subnet and gives me internet access.

 

Wan1 is set as static with the centurylink static ip, gateway of 192.168.1.1 and dns of 205.17.3.65(centurylink).

The link is up.

When I connect the centurylink modem to wan1 on the ER6120 and the laptop to the lan connection on the ER6120 

 

I disable and the enable the network connection so it refreshes the connection.

The laptop picks up an ip address in the 192.168.1 subnet.

It does not have internet access.

I can access the ER6120 at 192.168.1.1.

 

Why won't it give me an internet connection through the ER6120?

 

 

 

 

 

  @gjunk 

What you did is right. But, it is not recommended like the KJK said. A router(ER6120) behind a router(centurylink modem router). If you can connect directly to the centurylink, that would be great. If not, you set the modem router to bridge mode and connect ER6120 behind it.

For your case, config for LAN is good.

WAN is not right on ER6120.

If you choose Dynamic IP as the connection type on ER6120, you don't have to configure anything. Just plug and play.

If you use Static IP on ER6120, your WAN IP should be an IP from the LAN of Centurylink. > e.g. 192.168.0.2

Subnet should match with the LAN config of Centurylink. > 255.255.255.0

Gateway is the IP of Centurylink > 192.168.0.1

DNS, whatever the servers you prefer.