I'm just wondering if others are seeing issues with the DHCP Server on the Mikrotik OS and certain brands of devices obtaining IP addresses?

We are seeing that devices from certain manufacturers are not obtaining an IP address from our Mikrotik routers. When a static IP address is assigned to the unit, it works great. We are seeing this with certain DSL routers, the Motorola VOIP unit that Vonage provides and some DSL modem/router combos.

What appears to be happening is that the client device is requesting an IP address and the Mikrotik is responding, but the client doesn't like the response and does not take the address. After some research and packet traces, it looks like these devices are expecting a 328 byte reply packet and are not getting that, so they don't take the address.

Is anyone else seeing similar? Does anyone know of a way to change the reply packet size for the DHCP server portion of the Mikrotik? It looks like most devices are expecting a certain size of reply packet, but some are more strict than others.

Thanks,

Lance

In the DHCP standarts there is nothing mention that it should be 328bytes. In the standarts is written that the DHCP client should be able to receive reply packet with size up to 576bytes.
We don't have such device which doesn't work with our DHCP server. If you could give more info where the problem is then it could be fixed.

I'm just wondering if others are seeing issues with the DHCP Server on the Mikrotik OS and certain brands of devices obtaining IP addresses?

no.
did you try some other dhcp-server with theese devices?

We have the same issue with only MOTO devices so far. All the Vonage (MOTO devices) fail to obatin, but work with other DHCP server just fine. We deploy MOTO Canopy and get the same issue there. The unit gets an IP fine from a standard linux DHCP server, but not a tik box.

This is one main issue holding us up form deploying tik more widespread, we have had the problem from 2.7.12 to 2.8.12.

lee

Do you have multiple IP addresses on the DHCP server interface?

Yes, I do have multiple IPs on the interfaces in quesiton. Except for the problem I was having wiht my MOTO Vonage line. That only had a single IP on that particular interface.

Yes, I do have multiple IPs on the interfaces in quesiton. Except for the problem I was having wiht my MOTO Vonage line. That only had a single IP on that particular interface.

You should specify server IP under DHCP Server configuration.
DHCP Server uses first IP on Interface when sending the reply's and client wont have route to that IP.

Yes, I do have multiple IPs on the interfaces in quesiton. Except for the problem I was having wiht my MOTO Vonage line. That only had a single IP on that particular interface.

You should specify server IP under DHCP Server configuration.
DHCP Server uses first IP on Interface when sending the reply's and client wont have route to that IP.

I correct myself, it rarely has anything to do with route in this case. But still, setting server IP should help.

I also just noticed the issue when I got my router all plugged in. The box Vonage sent me would work fine with my Dlink for DHCP but the Mikrotik just wouldn't work somehow. Set it to static and it works fine. Does anyone know if not using DHCP will keep any UPNP from working properly?

Try HP Jet direct print servers... IE: 300Ex They wll not accept the lease.
The router will offer but the print server ignores it.

Craig