Unable to pull DHCP address on gateway

RouterOS General
1

I am trying to deploy a RB2011UiAS-2HnD-IN and cant seem to get the gateway interface to pull a DHCP address. Setup is as follows-

ISP cable modem > Ooma VOIP > RB2011UiAS-2HnD-IN

I have the Ooma VOIP “home network” interface configured as follows

IP- 44.128.0.1
Mask- 255.255.255.0
DHCP Pool- 44.128.0.2-44.128.0.2
DMZ- 44.128.0.2

The RB2011UiAS-2HnD-IN Ethernet gateway is running DHCP client.

When I connect the gateway interface of the RB2011UiAS-2HnD-IN to the “home” port of the Ooma the gateway will not pull a DHCP address. If I put the previous router back in place it pulls the 44.128.0.2 address and everything works fine. I have tried powering everything down and then powering up each device one at a time but no luck.

If I connect the previous router to the Ooma device and then plug the gateway interface of the RB2011UiAS-2HnD-IN into the old router the RB2011UiAS-2HnD-IN pulls a DHCP address on the gateway.

Any thoughts as to what might be going on?

2

A DHCP pool with only one usable address is not very good. If the server thinks the address is in use, and not by your device, then it won’t get the address. Can you make a larger pool and then specify the Mikrotik’s MAC address as a static lease?

3

I wish I were able to assign a static ip address to the MAC address of the gateway but the Ooma device does not allow for static ip assignment.

4

I wish I were able to. It does not appear the Ooma device allows for static reservation on the “home” interface.

5

Any ideas on what I should look for? I can’t seem to find anything wrong with the config.

6

Why not just make the Mikrotik static?

In the Ooma, Change this:
DHCP Pool- 44.128.0.2-44.128.0.2
to this:
DHCP Pool- 44.128.0.3-44.128.0.254

And In the Mikrotik, put this IP address on your wan interface:
44.128.0.2/24

And add this default GW:
0.0.0.0/0 gateway=44.128.0.1

And disable DHCP client on your wan interface.

Finally, put some valid DNS servers (e.g. 8.8.8.8 and 8.8.6.6 if you don’t mind using Google’s DNS service) into ip > dns settings so that your LAN will get DNS service.

This ‘should’ work. Remember that you’re now going to be subjecting all inside computers and devices to double nat.

I would be much more keen to put the Ooma behind the Mikrotik and have the Mikrotik be the only router.

7

I considered doing exactly as you said but ultimately decided to just put the Ooma behind the router and apply some QOS rules through the router. All seems to be working well. Thanks!