IPFire just for DHCP Server?

Hi all, quick question:
for reasons that are too complicated to write about here, I have been looking for a good DHCP server to run on a separate appliance in my network.

From what I’ve seen, IPFire provides the most variability / options in the Green DHCP server. So I’m thinking of using an older APU box to install IPFire and JUST use the DHCP server on the green interface to service my internal network.
This box would run as x.x.x.2 next to my IPFire firewall at x.x.x.1 - on the firewall, I would turn off the Green DHCP server, of course.

Is there any reason this won’t work (or isn’t recommended)?

Thank you!

To understand your case, you should elaborate a bit about the reasons.
Logically it is best to use DHCP server of the internet access IPFire.
I don’t know whether there are relations between the several functions of IPFire and his DHCP server, but it may be.

Regards,
Bernhard

You are looking for a DHCP? You can run Windows or Linux and just use this: Open DHCP Server download | SourceForge.net

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Hi @bbitsch, the reason has to do with the fact that my wife’s home office is physically connected to the rest of the house’s network as well as to my home office.

While the rest of the house uses a cable connection (on which sits IPFire as the firewall), she has a separate DSL connection via a FritzBox.
Her subnet is x.y.32.0/16 while the rest of the house uses x.y.30.0/16. Turning on the DHCP server on the Fritzbox AND in IPFire causes “random” DHCP assignments.

The idea was to have a centralized DHCP server that serves both my wife’s office as well as the rest of the house. A first look at the recommendation by @xperimental gives me hope that this is the best solution of all. I.e. a headless Linux on APU with Open DHCP Server on it. Will investigate.

x.y.30.0/16 and x.y.32.0/16 belong to the same network x.y.0.0/16!
For correctness only.

DHCP is Broadcast. You may not have 2 DHCP servers in the same (physically) network (without any NAT between both “sides”.

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Hi @bbitsch and @xperimental - you are both right, of course.
That is the reason I only want a single DHCP server in that network :slight_smile:

If I understand right, your installation consists of following networks:

  • WAN1 ( cable modem )
  • LAN1 (x.y.30.0/24 )
  • LAN2 (x.y.32.0/24 )
  • WAN2 ( DSL )

WAN1 is connected with IPFire to LAN1.
WAN2 is connected with a Fritzbox to LAN2.
LAN1 and LAN2 are physically connected ( over a router, a manged switch ? ) and constitute the network x.y.0.0/18.

You want to install a DHCP server for both networks ( the device has two NICs to differentiate ? ).

I think this task can be solved much easier, if we know more about the connection of the two subnets.

Hi @bbitsch, the APU has three ports, WAN (RED), LAN (GREEN) and a BLUE port I’m using for a smartmeter. The network is currently a class B so that yes - both the IPFire box and the Fritzbox are in the same network.

The reason this was set up is that I didn’t want to bother with a firewall between the Fritzbox side (my wife’s office) and the rest of the house. In case of a downed WAN, I turned off the DHCP server on the IPFire box and turned on the one on the Fritzbox.

That is pretty annoying, especially because not every device gets a new lease right away, and when they do it isn’t the same IP address as before (I have IP’s set by MAC address on the IPFire, not on the Fritzbox).

When an IPFire update failed (there was something about a wrongly named RAMdisk in the update, I believe), my firewall was unavailable and with it the DHCP server. Luckily, I was in the house (obviously, since I was updating it) - if that ever happend when I was travelling, my wife might not get internet.

So the idea is to use a separate device to run a DHCP server for all devices, though as I think of it, I’m not sure how I can force a lease reload after changing the router address in DHCP (from x.y.30.1 to x.y.32.1).

Thanks!

You can’t force a DHCP renew. DHCP has a lease time. This is the validity period for the network informations ( IP, gateway, … ).

Your installation uses switching of two WANs. I do not believe, that a extra DHCP server can accomplish this.