Hi everybody,
Had BT fibre installed recently and BT HomeHub 6 was supplied.
My 2860 was used before as ADSL modem directly.
What I want now is to use HH 6 just as a modem, and continue using 2860 and additional AP900s for wireless access, as before.
Is there any guide as how to configure and connect 2860 and HH 6 to talk to each other?
Thanks!

The HH6 doesn't have a modem only mode, so you won't be able to do this cleanly.

What's the reason you would want to use the HH over the 2860?

It is not my system, but my client's. In order to minimise any time wasting, with BT if something goes wrong ,
my idea was to just use BT HH6 as a modem. That way everything remains connected as before.
Is then somewhere a guide as how to switch off DHCP server on 2860 and connect to BT HH 6?
2860 will be used only as a switch and access point.
Thanks!

You can switch off the DHCP server under LAN > General Setup. The "Details Page" for the LAN. DHCP server is on the right where there is an option to disable it.

Thanks! Tried to do a proper set up but no luck.
Would appreciate your help.
Which port to use to connect to BT router/DHCP server, WAN 2 or LAN (e.g. 1) port?
How to enable one of the above to accept Internet connection?

I honestly.. honestly think you should simplify the set up and just have the 2860 for both the route and modem and just scrap the crappy HH.

You are just making it more difficult for the client and yourself. K.I.S.S

One questions and I can help you set up the whole thing..

Is this a Home or Business Fibre line?