Got new modem, Router 493g not giving internet access.

RouterOS Beginner Basics
1

Hey guys - I’ve run into an issue and could use some guidance.

We have a very simple setup. Netgear DOCSIS 3.0 modem in bridge mode, a Router 493g and two 48 port switches. The two switches provide out data/phones to all our classrooms and our 11 Ubiquiti AP’s.

Well, I was around when we did the first initial setup with the MicroTik router, but was busy doing other things while my coworker talked with the consultant on getting us setup. Yesterday, I upgraded our bandwidth with Comcast to 50/10 so we upgraded from a DOCSIS 2 to a DOCSIS 3 modem. I figured it would be a quick little hot swap and we’d be back online, but this is not the case. The new modem is installed and everything is exactly the same, but we can’t get out to the internet. Local LAN is fine and devices are getting IP addresses, as well and being able to ping each other back and fourth.

In our routers webfig, we have two bridge connections created. One is "Comcast’ and one is ‘LAN’. I changed the MAC address on the Comcast bridge settings to match our new router - rebooted, but still nothing.

I’m no wear near a pro with Networking but have a good understanding but I’m stumped on this one. What am I missing here? Thanks for your help in advance.

2

Hey
When you new connection came did you IP address for the modem not change. If so you would need to reconfigure the interface IP to the match. can you provide more info.

3

Well the default IP on the Modem is 10.1.10.1 (However out network is is running on C class network, currently 192.168.0.1-192.168.3.354 - router is set to 192.168.1.1/22)

But once I called Comcast and told them to put the modem in bridge mode, that IP address in no longer reachable and I can’t reach the interface. Do I need to hard reset the modem and change it to a class C IP address and then switch it to bridge mode?

4

You should be using 2 interfaces. 1 for your lan the local computers and once for the wan connected to the modem. If you are using winbox you can click on terminal and then type in ip address print this will tell you what IP address you have on each interface. You need to confirm that the ip address you have set on the interface connected to the modem corresponds to the informaion Comcast give you.

5

Correct. The LAN for our internal network looks be be working fine, transmitting and receiving no problem. The Comcast bridge interface is what is not transmitting at all.

When I execute that command it gives me the following:

Address : 192.168.1.1/22 **Network -**192.168.0.0 Interface - LAN

I’m going to guess that the Network 192.168.0.0 is my issue. I guess where I’m getting confused is in the bridge interface we created for router to modem doesn’t haven’t an option to assign an IP address (which would be the modems) But Comcast told me that our modem no longer has an IP because it is in bridge mode and all settings pass through to the modem.

Thanks for your help btw.

6

I just fixed it. I made a prior mistake.

In the Bridge Interface created for the modem/router connection, I set the MAC address as the modem - when it should have been left alone and had the MAC address of the router. We are back up and running, thanks for your help.