Hi guys,

I'm wondering, is it possible in any way, to make more than one DHCP Client for the same interface?

I only have one internet connection and therefor only one WAN port. My ISP can't deliver me an IP scoop that I can manage on my own (route it on my RB on my own), which means if I buy 5 IP's, the router need to show 5 MAC adresses to the modem/WAN port.

Is it possible or am I screwed?

Why can they not give you all 5 ips on the same mac address via static addressing and then you NAT them from there?

Why can they not give you all 5 ips on the same mac address via static addressing and then you NAT them from there?

I don't know why they can't do so, called them and they told me that they never would be able to do.
As far as I can see, they attach a mac address for each giving ip.
Lets say they give me following 5 ips:
1.1.1.5
1.1.1.6
1.1.1.7
1.1.1.8
1.1.1.9
All those would be listed through their web management. I can then release and renew between those, but only for each mac address that their DSL modem has registered (which is only one currently due to DHCP Client limitations on my MT).
Its seems like they can only attach one IP per mac address... pff..
Your idea with assign all ips to the same mac address is good and easy, but their techtician told me they won't able to.

Any ideas for a work around??

Can't you use virtual interfaces or make interfaces switched and assign IP-addresses to them? Don't know if the latter is applicable to ROS though, just some ideas.

Hav you tried creating Virtual Ethernet interfaces and bridging them together with the WAN interface?

Hav you tried creating Virtual Ethernet interfaces and bridging them together with the WAN interface?

This might actually work. I have never tried it. But I still can't understand why your ISP cant do this. Who is your ISP?

Hav you tried creating Virtual Ethernet interfaces and bridging them together with the WAN interface?

Sounds like something I have to try. Havn't think about the bridge part of it, so will give it a try in the weekend.

Hav you tried creating Virtual Ethernet interfaces and bridging them together with the WAN interface?

This might actually work. I have never tried it. But I still can't understand why your ISP cant do this. Who is your ISP?

My ISP is called Fullrate located in Denmark.

Hmm.. Can't figure it out, since I havn't worked that much with Bridging yet.
Could you please give a quick setup example?

I was also wondering how to achieve this. I did some testing with virtual interfaces and with interfaces in bridges, also with vlans in bridges and so on and I have not succeeded.

My opinion is that we would need to be able to add multiple mac addresses per one interface and after that be able to create multiple dhcp clients per one interface, each for different mac address. Otherwise it would not work correctly.

The problem continues with outogoing traffic as the sending mac and ip should be corresponding together, so the interface should correctly select the mac according the outgoing ip address.

I dont know how much deeply the mac address processing is in the nic hardware or software, if it is processed in drivers, it could be possible to make a driver that would allow that.

Maybe we can try to convince mikrotik to do some research and offer a solution. In case they succeed, it would be a great advantage over all other competitors on the market!

Normis (or others from mikrotik), if you read it, what do you think about?

ther is 2 way....

1. Use the force... It sounds stupid but untill now i havent figured way of doing this in mikrotik whitout hardwiring.

Make bridge of wan eth port and aditional ports of how many external ip you nead. (Bridge of 4 ports will give you 3 IP)
Connect WAN cable to port 1
Then make short cable and connect it to port 2 (witch is in bridge) to other port not in bridge. and setup DHCP on that port. thats all Make second cabel conect to 3 port and to free not in bridge.


2. buy switch and put it before mikrotik for not wasting mikrotik ports, then use same as 1 solution jus not use bride in mikrotik.

If somone know how t oachieve this inside mikrotik pls.... let me know... (trided vlans... wan bridgin ect...)

I'm running into the same thing in the US. I have 2 cable providers in our local area that are doing this.

1. Imon Communications
2. Mediacom Communications

Both will not give out /29 blocks any more so if we want more than 1 IP address, we have to add a switch or use the cable from one port to another. It would be nice if there was a way to stick a virtual interface on a bridge and grab a 2nd DHCP lease with a different MAC. I think we will see more and more ISPs doing the same thing in the future.

I'm also interested to get a solution. Hard wiring is an option, but it's kind of strange, to say the least.

Is there a way to achieve the goal in a more elegant manner?

I think this type of adding IPs by the ISP is wrong.
In my cases (different ISPs) I use one DHCP Client address or PPPoE Client for WAN and the the ISP Route all other IPs to my DHCP/PPPoE Assigned IP.
Then I can manualy add IPs to ip addresses or route designated (from ISP) addresses to my clients.

I cannot think of reason why any ISP could not do that. But they have to do it on they side.

Obviously, there is a number of ISPs out there that do not do it this way.

I don't understand why it is NOT possible to have multiple DHCP clients on a single physical interface in Mikrotik. There's an option to add a virtual interface, so it feels like I'm half way there. But I don't understand how to get an IP address with it... Maybe I'm just missing something obvious?!

If you mean Virtual Ethernet, it won't help you, it's for MetaRouter.

The feature is not currently available in RouterOS probably because it's a little unusual and I guess people didn't need it in the past. But it looks like times might have changed and my quick miniresearch shows that Linux can do it now: That gives you two new MAC addresses you can use with DHCP client. I did quick test with current Debian and it seems to work fine. But don't get too excited, it doesn't seem to exist for Linux kernel used by current RouterOS.

Thanks Sob,

Yes, I thought Virtual Ethernet is the key. Now I understand this is not the way to go.

If anyone from Mikrotik reads this thread, can this feature be added to the roadmap? Please! There definitely is a demand for this!

I get many DHCP clients on one interface by VRRP.

It helped me to this topic: http://forum.mikrotik.com/viewtopic.php ... r+solution

It works fine for 3 months.

sorry for my English