Hitron CGNV4 with Static IPs assigned by DHCP

[UmarFKhawaja]

I have Virgin Media Business broadband with 5 static IP addresses.

I would like the static IP addresses to be assigned automatically via the Hitron router's DHCP service to connecting devices on my internal network.

Is that possible?

I have tried setting up the router's LAN settings to assign the IP addresses via DHCP, but the PC (hardwired into the back of the router via a network cable) does not pick up the configuration.

If I assign an IP address from the my block of static IPs, the connection is established correctly, and I can access the internet.

Thanks in advance for any light you can shed on this issue. I cannot find any documentation on this letting me know what is possible and what is not.

[jbrennand]

This forum is intended for Residential customers rather than Business users as yiou use different equipment. There are some people on here who are "experts" in networking who should comment in due course.

VM here - will just refer you to the Buisness help line number

[jem101]

I’m not sure I fully understand what it is you are trying to do. The static IP addresses are public one and absolutely will never be allocated to the devices on your LAN, (they are on the wrong side of the router). At a guess, maybe, what you are after is for a particular device on your LAN to appear to have a different public IP address to another device, that can certainly be done but not with the VM (Hitron) hub, you will need a vastly more sophisticated firewall/router to do something like that.

[legacy1]

Guess Hitron with 5 static IP don't run a DHCP server which you will need to setup.

So if you have 194.168.0.0/29 so 194.168.0.1 would be the gateway so you have 5 static IP's so if you get a router how would you put that in a LAN...so 194.168.0.2 would be taken from for the WAN IP and gateway to 194.168.0.1...but you can't put a 194.168.0.1/29 on the LAN I guess you could do 194.168.0.5/30 giving you one WAN IP 194.168.0.6 but that a waste of IP space doing that...or go with a router with a bridge taking 194.168.0.2 with /29 to run a DHCP server giving you four wan IP's.

Really what VM should have done is used 172.16.0.0 - 172.31.255.255 as a gateway for the Static WAN IPs to route on so the gateway is 172.16.0.1 the IP in the WAN of the router is 172.16.0.2 the router LAN is 194.168.0.0/29 and you SNAT none LAN to WAN. 

[UmarFKhawaja]

Thanks John. I tried calling the Business number, but I am not even sure they understood what I was hoping to achieve.

[UmarFKhawaja]

What I was trying to achieve was fairly straight forward.

I have a Hitron router, which connects to the VMB network. I then have 2 devices connected to it directly, via wired ports at the back of it. One of them is a PC (let's call it A), and the other is a Google Wi Fi device (let's call it B).

Both of them are currently configured with static IP addreses.

The Google Wi Fi then provides a private network for all other devices (C, D, E, F, etc.).

I wanted to be able to configure the DHCP service built into the Hitron to provide IP addresses to A and B. Most DHCP services also support IP address reservations. That is the method I wanted to use to ensure A and B always get the same IP address.

The advantage was that I would not have to configure all devices explicitly.

It seems this is not possible, even though I am able to switch on the DHCP service in LAN settings on the Hitron router via its web interface.

[UmarFKhawaja]

The way the setup works is that the router gets assigned a dynamic IP address, but then it creates a tunnel.

If you get a package of 5 static IP addresses from VMB, VMB provide you with a subnet of 8 IP addresses, for example x.y.z.100 to x.y.z.107, with a subnet mask of 255.255.255.248.

Of these 8 IP addresses, only 5 are usable. 1 of them has to be used by the router itself (one end of the tunnel mentioned above), and the remaining 4 are usable by your own devices.

[jem101]

So you want the Hitron to automatically assign one of the public IP addresses to each of the two devices directly connected to it, yes?

If so then I'm afraid, you can't, it doesn't work like that, you need to manually assign an unused WAN address to the device and set it's G/W to be whatever address the Hitron itself has.

[legacy1]

You can run a DHCP server by a switch without using one of your WAN IP's to assign your WAN IP's.

Or you can get a ZyXEL USG like run it as a bridge with DHCP server.

Gateway 194.168.0.1
tunnel
Hitron
ZyXEL bridge 194.168.0.2/29 DHCP server for 194.168.0.3-194.168.0.6
your devices

[UmarFKhawaja]

Yeah, that's what the VMB engineer told me. It's just a shame because there is no reason why the DHCP service in the router couldn't do this job. In fact, it would be ideal for it. It is just that they have inhibited the DHCP function of the router.