DHCP problems - What is everyone using?

We cannot seem to get the A5 to pass DHCP properly. It hands out the IP, but the subnet mask is wrong and possibly the gateway. We are handing out addresses with the Mikrotik router the A5 is connected to.

The C5’s get IP’s but I’m not sure if they pass traffic. I can find that out but now we have to test in off hours.

We do this in a few other locations with other gear and in a few customer networks. The only time we have seen it NOT work was with a Ruckus AP after a MT firmware upgrade. We downgraded it and it worked but that same issue happened on a sonicwall upgrade with the same Ruckus AP, so I’m not ready to blame the Mikrotik router since all of our other routers have been upgraded with no issues with DHCP compatibility and other connected hardware.

Firmware should be the same on both A5 and C5, and the latest version possible. Over time, we have added encryption on management traffic between A5 and C5, so version differences could be a factor.

Another possibility is that traffic to the DHCP server requires a VLAN, and that it is stripped off by the A5 if you do not have VLAN passthrough enabled, or that the VLAN tag is replaced if you have per-SSID VLAN turned on.

If you’re using VLAN’s, the Mikroitk update has been causing problems. 6.38 caused the problem and it was fixed in 6.38.1 but all the Mikrotiks need to be same firmware. We had one on the other side of the client and it made it look like the AP had crashed because of the conflicting VLAN tagging from the different firmwares.

Does anyone out there successfully have a Mikrotik router handing out DHCP to clients via an A5?

We have gotten to the point where testing is disruptive to our clients and I’m just looking for a concrete answer of yes or no and if yes, “this is how we have done it”, “these are the exact steps”. any help would be appreciated.

I know there is tons of gear out there and MImosa can’t test for everything, but testing on Mimosa’s side involves investing in a $50 router. Testing on our side involves a $1500 AP and currently we have no spares on hand. (I know.) :flushed:

To clarify our needs, it’s nothing special. DHCP from the MT out via the A5, to the C5 and then whatever device is behind that be it a Dlink, Linksys, Windows PC etc.

Thanks in advance.

Yes, I am successfully running DHCP on a MikroTik router through an A5. It is nothing fancy, just a default DHCP server will do. No VLANs at this time. A5 gets a DHCP address, C5 gets a DHCP address, and customer router gets a DHCP address.

I have Option 82 turned on in most places too.

We are using DHCP for client routers that we do not have access to, but we only use statics for our antennas and assign certain IPs to clients. All DHCP is from a MikroTik router in the tower.

If someone connects a router to our network that we have not configured we have give them an IP that does not route out of our tower, then they call us and we figure out their MAC address and we do all the settings in the Mikrotik to get things working.

Currently I am not certain that we have any routers doing DHCP through a C5 to A5c, but we do have some routers that get their address connecting through a NSM5 to an A5. Those customers have not had any issues that they have reported to us.

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