BT Wholehome/Smarthub and DCHP query

[Jim-lad]

I have run a BT Wholhome (White Disks) setup for quite a few years now and found it to be a really good system. However, a recent hiccough has led me to query something. I know my BT Smarthub aka HH6 allocates DCHP for my Ethernet wired connections but doe the Wholehome master disk (now the WiFi router also allocate DCHP?) The reason I ask is that I have noticed a device using WiFi on the Wholehome network has a different IP address than that if I use Ethernet with that same device. Surely the IP address should be the same regardless of whether I choose WiFi or Ethernet?

[licquorice · Accepted solution]

No, WiFi  and Ethernet are different network interfaces and will thus have different IP addresses. Also, you can only have one DHCP server on a network otherwise chaos would ensue.

It's the interface, not the machine that has the IP address.

[Keith_Beddoe]

@Jim-lad 

A different IP address will be allocated to each MAC address, so a device which has both wired and wireless connections, would be given two IP addresses, as the MAC address for the Ethernet port would be different to the MAC address of the wireless card.

[Jim-lad]

@Keith_Beddoe @licquorice  thanks both for the replies. I think it's the first time I have noticed a different IP address for the same device. The odd thing with this particular device is that it cannot maintain an Ethernet connection when I have the Wholehome disk connected and acting as WiFi router but works without issue if the master disk is disconnected. It does however work perfectly as a WiFi device. It was this issue which first me me realise the device had two different IP addresses and I wondered if both the HH6 and WH disks were acting as routers and handing out DCHP x2 which as you say would cause chaos or at least double NAT problems.